How to Optimize Fertility in Males & Females

welcome to the huberman Lab podcast where we discuss science and science-based tools for everyday [Music] life I'm Andrew huberman and I'm a professor of neurobiology and Opthalmology at Stanford school of medicine today we are discussing fertility we will discuss male fertility and female fertility and I should mention that today's discussion is not just for people who are seeking to conceive children or who want to know how their children were conceived but it's really for everybody and I say that because it is the story of all of us all of us are here because a specialized set of cells called germ cells that is the sperm and the Egg and I'll make it very clear why they're called germ cells a little bit later has nothing to do with infection but it's because a sperm cell and an egg cell arrived at one another either in Vivo inside of our mother or in vitro so-called invitro fertilization and then were implanted into our mother and became us and so so understanding the process of how the egg cell and the sperm cell came to be is really the key to understanding how that fertilization process came to be I know everyone's thinking I know how fertilization occurs it occurs through sexual intercourse and so on and we'll talk a little bit about that but I promise you that if you understand the menstrual cycle and the menstrual cycle in today's conversation can best be thought of as a biological cycle that occurs in females that allows the potential for fertilization by the sperm because that's really what it is and it's a beautifully orchestrated process that I'll describe to you and I should say all people males and females should really understand how the menstrual cycle works how it impacts fertilization but also how it impacts the brain and body Behavior psychology Etc and we will also talk about spermatogenesis how sperm cells come to be and how they arrive that is how they swim to the egg and the incredible interplay between the biology of the sperm and the biology of the egg leads to this incredible thing that we call embryogenesis and the birth of the child and of course the development of that child into an infant a toddler an adolescent a teen and an adult today's discussion again is not just for those of you that are seeking to have children and I say that because when you look at the data you look at the literature on LUN vity and vitality two themes in biology that often times people lump together but aren't always the same for instance there are a lot of things that we can do to increase our Vitality that actually can harm our longevity but there are a subset of biological rules and mechanisms that when aligned allow us to maximize both our vitality and our longevity and I think it's fair to say that all of those mechanisms and tools are housed in the discussion around maximizing fertility and that's true whether or not you're male or female in other words if you want children or if you don't if you already have children or if you don't understanding how fertility and fertilization occurs in the brain and body will allow you to maximize Your vitality and Longevity and of course today's discussion will provide an understanding of the biology and many actionable tools that will also help you conceive children if that's your wish so of course as is characteristic of this podcast we will discuss science-based tools including behavioral tools both the dos and the don'ts and we will discuss nutrition-based tools and supplementation based tools and some other practices including things like acupuncture which have quite good data to support them in terms of improving fertility and we will discuss why those certain practices can work and we will discuss prescription drugs that your doctor can prescribe to you if for instance you have a deficit at the level of hormone produ uction or neurotransmitter production at the level of the brain or the pituitary gland I'll explain what all of those things are soon or the gonads the ovary and the testes in females and males respectively Again by the end of today's episode you will have a lot of knowledge and actionable tools related to maximizing fertility and you will have a lot of knowledge and actionable tools related to maximizing vitality and Longevity before we begin I'd like to emphasize that this podcast is separate from my teaching and research roles at Stanford it is however part of my desire and effort to bring zero cost to Consumer information about science and science related tools to the general public in keeping with that theme I'd like to thank the sponsors of today's podcast our first sponsor is Maui Nei Meats Maui Nei Meats I can confidently say are the most nutrient DSE and delicious red meat available Maui Nei spent nearly a decade building a USDA certified wild harvesting system to help balance invasive deer populations on the island of Maui the solution they built turns the proliferation of an invasive species into a wide range of 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more importantly it's about producing offspring that contain the genetic components of both parents and indeed contain half of the genes from one parent and half of the genes from another parent now there are two general types of cells in the body the most common types of cells in the body are called somatic cells so this would be all the cells in your body except the egg in females and the sperm in males the egg in females and the sperm in males are part of what's called The Germ line and again it has has nothing to do with infection it's just that the cells of the germ line have genes that cannot be modified by the behavior of the individual that houses those genes what do I mean by that well if I were to tell you that by exercising you can improve mitochondrial function you can change hormones um by reducing stress you can reduce cortisol by um hitting puberty for instance uh you will have the secretion of hormones that then change gene expression in other cells leading to development of body hair facial hair deepening The Voice breast growth Etc you'd say okay great yeah that all makes perfect sense but that's all occurring in the so-called somatic cells The Germ cells or the germline cells that is the egg and the sperm are a very unique and protected set of cells that are generated in a particular way and whose genetic components are not modifiable by experience and when you take a step back and you think about it you say oh that's right there's no reason to think that exercising will make the children that you have not yet had stronger and of course not well why is that well that's because there is a barrier between the genes of The Germ line cells and behaviors they cannot be modified by behaviors and the various things that you do in your lifetime now I suppose there's an exception in the negative Direction and what I'm referring to here is if you were to say be exposed to a chemical that could mutate the DNA of your egg or sperm or or if you were to fertilize an embryo at a in a certain way or at a certain stage of life that it got an extra chromosome for instance we'll talk about this a little bit later well then of course you could end up with offspring that have modified DNA that don't Faithfully represent half of the genes from Mom and half of the genes from Dad but that's not the same as specific behaviors modifying the genes of those cells the sperm and the egg cells in a way that improves The Offspring Okay so the key first thing to understand today is that there's a distinction between somatic cells which is the vast majority of cells in your body and the so-called germline cells which are the egg in the sperm the egg in the sperm are these highly protected populations of cells that in females actually come to be during embryogenesis okay so for all females out there you generate what today I'm going to refer to as a vault of cells you have a vault of of eggs that are your germline those eggs all contain all the chromosomes of your DNA so it's going to be as most of you know there are 23 chromosomes and chromosomes consist in pairs so the way to think about this is each pair is one strand and you have 22 so-called autosomes and then you have one sex chromosome the sex chromosome would be either X or Y so in a female they have two X chromosomes so when each one of the eggs that a woman has and that she's had since she was an embryo and that's contained in this Vault those eggs are of course going to be very immature at Birth right she hasn't undergone puberty yet and certainly as an embryo she has an undergone puberty and those cells are going to contain 23 pairs of chromosomes okay this is very important 23 pairs of chromosomes the chromosomes are essentially the wrapped up DNA that contains all the genetic information to create any cell type in the body and actually to create an entirely new individual now there are 23 pairs of chromosomes 22 of which are called autosomes okay if that doesn't does make sense to you just remember autosome okay there's 22 of them and then there's one so-called sex chromosome the sex chromosomes are either X or Y but this is a female so she's going to have 23 pairs of chromosomes and she's going to have two X chromosomes for the sex chromosomes okay if this is already confusing to you don't worry I'll make it very clear how this all relates to fertility and how it relates to chromosomal segregation and a bunch of things that I think maybe you've heard of and that perhaps um were opaque to you but I promise to make them clear just understand that within each of those eggs they have 23 pairs of chromosomes and for those of you that like nomenclature I'll tell you that those cells are considered diploid they're called the diploid and that means that they have 23 pairs of chromosomes as distinguish from cells that are haid where there's only one set of those 23 chromosomes so instead of 23 pairs there's only 23 chromosomes we'll we'll come back to haid cells a little bit later okay so when a female is born she has all these eggs in the reserve in this Vault that she'll have for her entire life she's not going to make any more but they are very very immature so when a woman is in embryogenesis she develops these very immature eggs okay today we're also going to talk about follicles and um we will be careful to distinguish follicles from eggs they're often talked about interchangeably online and elsewhere and even by fertility docks and OBGYNs but we'll right now we're just talking about the egg cells okay the eggs themselves which are cells now the goal of fertilization is to bring that egg cell into close enough proximity that it can be fertilized by a single sperm cell and that sperm cell will bring 23 chromosomes as well that include just as in the female egg it'll have 22 autosomes and one sex chromosome and in the male that sex chromosome can either be an X chromosome which then would give rise to female Offspring or a y chromosome which would give rise to male offspring and today we're not talking about sexual differentiation that's a topic of a previous and yet another future episode but just to give you a sense of how X chromosomes and Y chromosomes can actually accomplish that sexual differentiation both of body and brain I'll just mention in two sentences that for instance if there's a y chromosome as opposed to an X chromosome that Y chromosome contains genes that suppress for instance the development of female genitalia and thereby give rise to male genitalia so rather than the formation of clitterus is the formation of a penis and rather the formation of ovaries the formation of a testes okay so that's more directed towards sexual differentiation we're not going to get into that right now we'll get into that in a future episode but even if you're only tracking about 10% of what I'm saying right now I promise you're doing great if you're tracking more than 10% well then you're doing terrifically well because the essence of fertility fertilization is to bring together that haid cell that is the sperm that only has 23 chromosomes but not pairs of chromosomes right because that's the DNA from Dad together with the egg which is I told you already has 23 pairs of chromosomes so part of the fertilization process has to be to get rid of one half of those 23 pairs in the female you got to get rid of it and you have to get the in the sperm in proximity so that the egg can potentially be fertilized by the sperm bringing the DNA the 23 single strands of chromosomes from Dad into a cell that has 23 single strands from Mom okay so I'm I realize I'm probably being a little bit repetitive here but I want everyone to understand this because it really frames up fertility and reproduction in the proper way we've got a cell from Mom the egg which has 23 pairs of chromosomes we need to get rid of one set of those pairs so that there's only 23 chromosomes we need to get rid of half of those chromosomes and then we need to bring that cell together physically with the sperm cell that contains the 23 chromosomal strands from Dad and we need to bring those together so that you get 23 chromosomal pairs from Dad and 23 chromosomal pairs from Mom and in doing so you create a cell which then becomes multiple cells that's going to be the developing embryo that has half the genes for Mom and half the genes from Dad so I hope that's clear that is the biological logic which I realize is a bit of a tongue twister but um forgive me it is the most accurate way to describe this process we're trying to bring together the 23 single strands of chromosomes from Dad and the 23 single strands of chromosomes from mom into the same cell now that requires a literal physical contact and pairing of the two cells but as I mentioned before all these eggs in mom are sitting in a vault and they're very very immature so the ovulatory cycle and the menstrual cycle are really about first eliminating half of the chromosomal pairs in that 23 sets of chromosomes and not getting rid of for instance half you know just going one to uh you know 1 to 11 or and then or 12 to to 23 that's not the goal the goal is to have chromosomes 1 2 3 4 5 6 all the way up to 23 but only to have half of the chromosomes there and to bring that cell together with the sperm cell physically then allow them to fuse and allow the chromosomes from Dad and the chromosomes from Mom to fuse within a single cell and duplicate into cells that contain half of the chromosomes from Dad and half of the chromosomes from Mom that's what the ovulatory and menstrual cycle are really all about so when thinking about it way I'd like to just initiate the discussion by focusing first on the female component or the Egg component of fertility and fertilization as I mentioned before a female has all the eggs albeit very immature eggs that she's going to have at the time that she's born now puberty will happen at some point and will allow the ovulatory and the menstrual cycle to commence now one question that you perhaps are asking is what controls the onset of puberty and there there are a number of different results Each of which could be an entire episode of a podcast on its own but I'll just highlight a few things that we know about the onset of menes or menstration or it's sometimes also called menarchy all right one thing that you'll notice about today's discussion is that if you were to take any number of your notes online and put them into a a search function that you would see a lot of different language used for the same thing so for instance some people will talk about the egg and the follicle as the same thing even though they are not I'll explain the difference soon some people will talk about menes or menstration or menarchy is the exact same thing and in fact they are not the exact same thing but oftentimes these uh words are used interchangeably I'll do my best today to not overload you with nomenclature but rather to use the most commonly used terms for the different aspects of fertility and fertilization but when it comes to the onset of puberty first of all most of you have probably heard that the onset of puberty is happening much earlier in females now than it was some years ago and in fact that is the case and I'll talk about some statistics related to this um which are pretty striking but don't necessarily point to anything detrimental it doesn't necessarily mean that something bad is happening what do we know for sure well we know that there are a number of signals that come both through the brain and through the body and more likely both in order to control the onset of puberty in females a couple of examples the first is a mechanis one we know for instance that the entire process of the ovulatory and menstrual cycle is initiated from the brain we're going to get into this in a lot more detail in a few minutes but there's a certain number of hormones and neurotransmitters that are communicated from the brain a structure called the hypothalamus which roughly sits above the roof of your mouth and that communicates with a gland an endocrine or hormone relasing gland called the pituitary gland the pituitary gland looks like a a stock um that essentially extends out of the brain it's also located not far from uh your the roof of your mouth and that has two sort of um small marble or grape-sized um uh protrusions that the anterior pituitary and the posterior pituitary and they release different hormones into the bloodstream puberty is in part controlled by the fact that up until puberty there are neurons in the hypothalamus that release a neurotransmitter called Gaba which is inhibit and that prevents the neurons in the hypothalamus from releasing a very important hormone called gatot tropen releasing hormone or GNR so the first thing I'd really like everyone to know and commit to memory today is very easy GNR stands for gatot tropin releasing hormone this comes from the brain and will communicate to the pituitary to release certain hormones prior to puberty in both males and females there are neurons in the brain that are actively suppressing the neurons that release G&R it's like no puberty no puberty no puberty can't have puberty can't have puberty and in fact those cells are releasing this neurotransmitter called Gaba because it's inhibitory it prevents the firing of those neurons okay so puberty is actively suppressed up until a certain point it's also actively suppressed at least in some species and we think at least partially in humans by the tonic release that means the ongoing release Around the Clock of a hormone called melatonin later in life in fact after puberty melatonin will be secreted only in the dark phase of each night and around the time that one goes to sleep but in children and in particular in children prior to puberty melatonin is released more or less constantly now melatonin isn't the only source of suppression of puberty it's also these neural mechanisms involving Gaba but it is certainly a great candidate for one of the reasons why puberty doesn't generally tend to happen at say H4 or H5 that would be very unusual another component of suppression of puberty is that typically in children they have relatively low body fat stores why is this important well we know that one of the things that can trigger the onset of puberty in particular in females is that when enough body fat accumulates that body fat releases a hormone called leptin and that hormone leptin travels in the bloodstream across the bloodb brain barrier and goes to the hypothalamus and can trigger the onset of puberty by activating the neurons that release gonadotropin relasing hormone so many people believe that one of the reasons that puberty is happening earlier and earlier in females is because of the accumulation of more body fat at younger ages than was observed 30 or 40 and certainly 100 years ago now I can already imagine a number of people are thinking oh this must relate to the Obesity crisis and indeed there is a crisis of obesity obesity uh is something that is causing all sorts of um problems with People's Health at various levels brain and body and that is far more frequent today than it was even 20 years ago so it is indeed a crisis because it has enormous detrimental effects for so many aspects of of brain and body Health and Longevity but this whole process of thinking about body fat signaling leap into the hypothalamus and the onset of puberty doesn't necessarily have to do with the Obesity crisis it might relate but it could also relate to for instance improved nutrition which is allowing body fat stores to accumulate maybe not to the level of obesity but to accumulate earlier and at younger ages in females which is then causing earlier puberty in females to just highlight how that might be possible I want to review some data that talk about the onset of menes menstration that is puberty in females according to Country and according to age over the last 100 or more years so what are the general Trends in terms of the onset of puberty and females well that's an easy one to answer over the last 100 years or so the onset of puberty has been occurring much earlier with each passing decade it's really an incredible set of Statistics um I'll I will provide a link to these data since I know a number of you are listening and not just watching on YouTube um this is from a study in which the onset of puberty has been analyzed from as early as the 1850s right in certain countries there are data on that out to the 1970s and in other count starting at about 1900 um extending out to about 1990 these are ongoing collections of data but just to give you a sense how the data are falling out in a couple of different countries just to give you a a flavor but for those of you listening and for those of you watching the essence of all of these findings is that puberty is happening much much earlier with each passing decade so for instance in the United States around 1900 or 1903 the average age of menur the onset of puberty in females was about 14 years old whereas in 1990 the average age is 11 so that's a pretty significant um we can say acceleration of the onset of puberty now of course these are averages so there will be exceptions there's a distribution of data today still there will be uh young females who will undergo puberty at age 11 or 10 or maybe even nine in others who will undergo puberty at age 13 14 maybe even 16 or 17 however if we look at for instance the data from Norway which dates back quite far they have excellent recordkeeping to 1850 what we see is that the average age of the onset of female puberty in 1850 in Norway was 17 years old whereas in 1970 it's 13 years old so this is a dramatic acceleration of the onset of puberty and you see a similar Trend in other countries as well so if we were to look in uh for instance in the UK um they have a a smaller data set um meaning it only extends back to about 1940 but the average age of the onset of puberty in the UK uh in 1940 was 13 12 years old again this is just uh for females and in 1970 it was closer to 13 with a trend towards declining even further Unfortunately they didn't continue to collect data out to 2022 and as a final point if we were to look at for instance in uh Germany and Finland uh the average uh onset of puberty in 1870 was 165 years old uh by 1940 was down to 13 and a half years old so all of these data have borne out over and over again regardless of location in the world which is important because when you start to think about the Obesity crisis you could say well that's mainly in developed countries believe it or not or perhaps not surprisingly and maybe it has to do with the Obesity crisis and yet I don't think we can conclude that at all something is happening however it could be increased body fat stores due to overeating and obesity however it could also be unrelated to obesity it could be for instance improved nutrition and the availab availability of quality nutrition which can signal the maturation of the brain and body mechanisms that trigger the onset of puberty ovulatory cycle and menstration so we want to be very careful about leaping to conclusions about what these Trends mean but the trends themselves are very very apparent and as a final point I should also mention that there are are a number of different behavioral and psychosocial as they're called interactions that can influence puberty as well this has been most strikingly observed in animals and so I don't want anyone to be alarmed or to LEAP to any great conclusions about the onset of timing of puberty in humans but I'd be remiss if I didn't tell you about a certain result which shows that if a young female is exposed to the odor not necessarily the phermones right there's a distinction between odors that we perceive and phermones which are subconscious right that we don't actively perceive but that can impact our biology and pheromone effects in humans are very controversial but we know for instance that if you take a female animal and there's some evidence from humans that if you take a young prepubertal female and you expose her to the scent of a reproductively competent male for series of days but maybe even as short as a few hours and she is also not regularly being exposed to the scent of her father that she can undergo puberty earlier that's right there is something about the odor Andor phermones or perhaps something else that occurs when a young prepuberal female is in the has a father that she's in regular contact with he wouldn't necessarily have to live at home but that is around a lot that her his smell excuse me is registered by her biological systems that I I don't want to say protects because it kind of skews the uh the veilance of the conversation but that that offsets or buffers the otherwise observed effect which is that the scent of a reproductively competent male if it's present often enough or perhaps intensely enough that it can trigger the onset of puberty in that female in other words the scent of a of a male that is not the father and we think also that is not biologically related to her can trigger earlier onset of puberty and that effect can at least be partially buffered by her being in the presence of the scent from her biological father now some of you are probably already leaping to conclusions about what this means you know should you U not allow your daughter to be exposed to any males who are of reproductive age Etc that's is certainly not what I'm saying there's a huge number of considerations that um that go into that calculation for everybody and circumstances Etc but the point is that the odors of individuals both related in particular closely related and non-related individuals can shape the neural systems and the hormone systems that can trigger the onset of puberty or suppress the onset of puberty so whether or not we're talking about onset of puberty at this age or that age and whether or not biologically related male or non-biologically related male sense around Etc the thing I want everyone to know is that at some point during development typically nowadays between the ages of 11 and 15 or so again there's variability there the suppression of gonadotropin releasing hormone released from the hypothalamus is removed and then gonadotropin releasing hormone can activate cells within the pituitary and if you really want to know it's the anterior pituitary in particular and then the anterior pituitary gland which sits at and kind of bridges the brain and the body because it allows the release of hormones into the bloodstream that anterior pituitary is going to release two key hormones that everyone should know the name of and what they do and when I say everyone I mean males and females need to know about these hormones because they have an active role in both males and females and of course you should want to know and should know about the biology of everyone on the planet in my opinion because it tells you a lot more about humans than if you just focus on your own biology but those two hormones are called lutenizing hormones which is abbreviated LH and follicle stimulating hormone which is abbreviated FSH okay so the the simple picture that you need to have in your mind is gonadotropin releasing hormone from the brain from the hypothalamus in particular is causing the release of lutenizing hormone and follicle stimulating hormone GnRH stimulates LH lutenizing hormone and follicle stimulating hormone FSH LH and FSH travel in the blood and can access all the cells and tissues of the body this is one of the incredible things about hormones is that many hormones and LH and FSH are included in this group can travel into cells and they can actually change the genetic expression of those cells they can change which genes are turned on and which genes are turned off and they can also attach to the surface of those cells and make those cells take on different properties so they can mature those cells so for instance a good example this outside of the context we've been talking about is the hormone testosterone can travel to the hair follicle and can stimulate changes in the genes of the cells of the hair follicle that can make hair grow a different hormone estrogen can travel to the cells of the breast tissue and activate genes that control enlargement of the cells of the breast tissue prolactin a different hormone can travel to the mamory ducts and control the production and the secretion of milk and in males that can actually happen in certain cases although it's rare but prolactin can also travel to areas of the brain that control libido for instance and just so you'll never forget it males um elevated levels of prolactin are actually what set the refractory period after ejaculation and prevent erection for some period of time so you'll never forget prolactin um the point being that different hormones have different effects on different cells depending on what cells those are right estrogen or estrad is going to have different effects on the breast tissue than it would on skin although it has effects on both similarly when LH and FSH luteinizing hormone and follicle stimulating hormone travel in the blood to the gonad and the gonad is an ovary it will have a certain set of consequences and when luteinizing hormone and follicle stimulating hormone travel in the blood to a gonad and that gonad happens to be a testy then it will have a different set of biological implications so let's focus now on what happens when LH and FSH arrive at the ovary and let's assume now that we're talking about a female who has already undergone puberty or perhaps we could even frame this in the context of a female who is about to undergo puberty FSH and LH are now able to be released because she's undergoing puberty but the same set of processes essentially would occur for any point from puberty onward until menopause which is the depletion of that Vault that ovarian reserve of all those immature eggs I'd like to take a brief break and acknowledge our sponsor athletic greens athletic greens is an all-in-one vitamin mineral probiotic drink that also contains digestive enzymes and adaptogens I started taking athletic Greens Way back in 2012 so that's 10 years now of taking athletic greens every single day so I'm delighted that they're sponsoring this podcast the reason I started taking athletic greens and the reason I still take athletic greens is that it covers all of my foundational nutritional needs so whether or not I'm eating well or enough or not I'm sure that I'm covering all of my needs for vitamins minerals probiotics adaptogens to combat stress and the digestive enzymes really help my digestion I just feel much better when I'm drinking athletic greens if you'd like to 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and the DNA of mom so the obligatory menstrual cycle occurs when luteinizing hormone and follicle stimulating hormone have been released and the ovulatory menstrual cycle and here I have to kind of pick what I want to call it um I guess to be really accurate we would just call it the female reproductive cycle but that includes underneath it but the menstrual cycle as it's sometimes called and the ovulatory cycle so you decide I'm going to interchangeably discuss the ovulatory cycle and the menstrual cycle the problem is when you say menstration people often think about just the period the shedding of the uterine lining when fertilization has not occurred so if I start saying ovulatory cycle just keep in mind I'm referring to the entire thing now this is probably also a good opportunity to say that if you heard that the ovulatory menstrual cycle is 28 days long that's true in some cases but that's not always true it's on average 28 days long there are some females for which the ovulatory cycle will be shorter can be as short as 21 days and other females for which it will be 35 days long shorter than 21 days and longer than 35 days is rare although it does occur one of the key things when thinking about fertility is if you talk to OBGYNs who are f fused on fertility which I have in anticipation of this episode they'll tell you that whether or not your cycle is 21 days long or 35 days long is not as much of an issue necessarily unless it's happening to become much shorter or much longer in a kind of erratic way so if you're somebody who's consistently had 23-day long cycles and all of a sudden you're having 30-day long Cycles that's not necessarily an indication of anything bad but if it's 21 days 1 month and it's 30 days the next month and that's 17 days the next month or even if it's always falling within that 21 to 35 day long cycle but it's very variable from each month or every other month or so you probably want to talk to your OBGYN because that could indicate a number of different things which things could it indicate well that will become clear as I spell out the biology in a bit more detail okay but this idea that the menstrual cycle ovulatory cycle is always 28 days that's just false that's just not true I should also mention that there is a common misconception that because the average menstrual cycle is 28 days indeed the average is 28 days and the lunar cycle is 28 days and of course there is real biology to support the fact that the lunar cycle can in fact impact certain aspects of human behavior it does and we'll talk about lunar cycles in a future episode but there is zero data to support the idea that the menstrual cycle and the lunar cycle are linked in any kind of causal way I'm sorry to break it to you the lunar cycle and the tidal Cycles at the ocean are definitely linked in ways that are super interesting related to the tilt of the earth and the pull of gravity of different planets and it's an incredible story into itself but the lunar cycle and the menstrual cycle despite having some weak correlation in terms of their their gen their duration or their so-call periodicity no pun intended well there's no causal relationship whatsoever between the lunar cycle and the menstrual cycle if any of you are aware of any real data that conflict with what I just said please put that in the comment section on YouTube um but this is pretty well established as as far as I know okay so we need to bring together the so-called haid cont contents the 23 individual strands of of chromosomes from the egg to a place in a position where it could potentially be fertilized by the male so what happens luteinizing hormone and follicle stimulating hormone travel to the ovary these hormones are able to access the ovary there's a lot of blood apply to the ovary and FSH and LH arrive at the ovary the ovary has this Vault this ovarian reserve of immature cells they reside within what are called follicles the follicles are little spherical packages that can potentially provide a nice environment for those eggs to mature and when FSH in particular arrives at the ovary a small number of those follicles will split off from the reserve they will exit the Vault and they will undergo maturation and the key player here is follicle stimulating hormone and the first 14 days of the menstrual ovulatory cycle is referred to as the folicular phase because of this relationship between FSH triggering the maturation of a subset of follicles now typically in the context of a 28 day or so ovulatory menstrual cycle day one is designated as the first day of the period of the shedding of the uterine lining from the previous ovulatory menstrual cycle in which fertilization did not occur okay so day one is when the period initiates it is Days 1 through 14 approximately right because here we're just considering the average of a 28 day cycle but it could be longer could be shorter but the first half of that cycle is the so-called follicular phase FSH has triggered the departure of a subset of these follicles that contain immature eggs and it is triggering the maturation of those eggs luteinizing hormone is also present but also at relatively low levels and it's during the first half of this ovulatory menstrual cycle that the main goal is to get those follicles to mature so inside of those follicles the egg is developing it's growing it's maturing and in doing so it's also making its own hormones this I think is one of the most elegant aspects of the ovulatory menstrual cycle that in a few minutes you'll learn about something which still to this day even though I've known about this stuff for for decades now because of my training still just blows my mind that you have one hormone follicle stimulating hormone triggering the maturation of some eggs inside of some follicles and then those follicles themselves making another hormone that furthers the process and then soon as you'll learn create a hormone to trigger the second half of the process just a beautiful Symphony of expression of different genes and different hormon hormones to make everything work as optimally as possible so as these different follicles mature somehow and we still don't know exactly how one of those follicles containing an egg gets selected it's either because it matures the fastest or there's something about it that is still not completely understood that allows it to be selected and all the other follicles that are maturing degenerate and die and they're gone they don't go back into the ovari Reserve they are now depleted from that bank account that is the ovarian reserve they die off but that single egg that keep in mind contains 23 pairs of chromosomes right we haven't gotten rid of one half of those 23 sets of chromosomes yet but that one will continue to mature and then at some point that egg will start to undergo a process in which those chromosomes are pulled apart by little components within the egg called spindles they literally have a physical pulling of the chromosomes apart so now those 23 pairs are no longer attached to one another at the middle like they were before like two beads of of strings or I should say 23 short strands of beads that were at once connected to one another now are pulled apart so that you have 23 chromosomes on each side but they're pulled apart from one another right so that diploid cell is now starting to become a cell in which half of the chromosomes half of those 23 pairs are physically pulled away from the others and then the egg actually starts to form its own what we call an involution of membrane around those 23 pairs one set of them and encapsulates them so you've sort of got an egg with two parts where the two sets of chromosomes two sets of 23 chromosomes are now separate from one another inside of the egg and then one of those actually gets ejected from the egg and the name of that thing that gets ejected it's sort of like the little H pod is how I imagine it um you know from from Star Wars you know from any kind of uh Space Odyssey movie where something is ready to happen you know the little Hub pod shoots out of the ship well that 23 paars is now ejected from the egg it's called the polar body and that's going to degenerate it's going to go away and in doing so take it the egg cell which was once Diplo it had 23 pairs of chromosomes and making it hloy and now what you've got in ideal circumstances is a beautifully pristine egg that was selected for and has 23 single strands of chromosomes 22 autosomes and one sex chromosome and that sex chromosome is going to be an ex chromosome almost with certainty because female mother is creating that egg so then the egg that contains just the appropriate 23 single STP stranded chromosomes is going to fuse with the wall of the ovary and that egg will be released and Will Travel into the fallopian tube now we'll get back to that egg in a few moments but that process which represents the first half of the ovulatory menstrual cycle again was triggered by FSH and to some extent leutinizing hormone but it is the ongoing maturation of that egg which also causes the production of estrogen which allows that whole process to occur and you could say why well the answer to the why is a very important biological principle that we are going to return to in a number of different context today both as reference to female and male fertility and the principle is a so-called negative feedback so when estrogen is present at relatively low levels in females in the ovary as it is during the development of these eggs some of that estrogen of course is going to exit the ovary it's going to go into the bloodstream and it's going to travel back to the pituitary now the pituitary can release things like follicle stimulating hormone and lutenizing hormone but the way I'd like you to think about the pituitary for sake of feedback loops is that it's sort of like a thermometer that you would put into a pool like a backyard pool that is attached to the heater and for instance if you were to put a thermometer into a pool that you would like to keep at 70° and the temperature of that pool is 60° well then that thermometer ought to trigger some sort of mechanism where the pool would heat up until the temperature of the pool hit 70° and then it should trigger that thermometer to turn off the heating system okay that's kind have a negative feedback system that would keep the temperature more or less correct that's a lot of the way that the systems related to estrogen and also testosterone and these different things like luteinizing hormone and follicle stimulating hormone work as well typically when the level of a hormone is too high then it shuts down the production of the hormones that would trigger further production of that hormone I know that's a mouthful it's a lot to think about and some of you are probably thinking whoa I'm getting dizzy now with Biology but I promise you can understand this in females when estrogen is relatively low but not zero but is relatively low during that first follicular half of the ovulatory cycle it actually triggers negative feedback on LH and FSH so that not too much is produced but then just prior to ovulation the levels of estrogen and the levels of some other hormones from those eggs right you have the eggs producing estrogen themselves gets high enough that it actually triggers a positive feedback loop on the pituitary so the pituitary is is essentially observing the amount of estrogen in the bloodstream produced by the ovary and the amount of estrogen towards the end of the second half of the menstrual cycle has increased and triggers a positive feedback loop it triggers the pituitary to release more FSH and LH and that helps trigger ovulation okay that deployment or the release of that one mature proper selected egg with that's hloy with the 23 individual pairs of chromosomes into the fallopian tube so let's just back up really quickly and just kind of summarize what's happened gonadotropin releasing hormone from the hypothalamus triggers the release of follicle stimulating hormone and luteinizing hormone that travels to the ovary triggers the release of a subset of immature follicles with immature eggs those immature follicles and immature eggs start to mature start to grow because of the presence of follicle stimulating hormone the growth of those eggs themselves increases estrogen as the estrogen starts to accumulate in the environment some of that travels back to the pituitary and when levels of estrogen arriving at the pituitary are relatively low the pituitary says oh we don't need to release any more follicle stimulating and luteinizing hormone however at some point just prior to ovulation enough estrogen has been produced by that one single selected mature egg and some of the other follicles around it that we're maturing but then since died off that the estrogen triggers a positive feedback loop the ptary says okay and releases more follicle stimulating hormone and luteinizing hormone and Bam the egg which has the proper genetic components sets off out of the ovary and into the fallopian tube so-called ovulation has begun okay that itself what I just described constitutes the first half of the ovulatory menstrual cycle which we call the follicular phase and it's marked by the presence of FSH and some other things but we can really think about it as marked by FSH from the pituitary and by estrogen or estrad made within the ovary okay then comes the second half of the ovulatory menstrual cycle which I personally think is one of the coolest mechanisms in all of biology which is that remember the follicle that housed that one egg that was the selected egg that became the mature egg and that follicle which no longer contains the egg because the egg took off and ovulated is called the Corpus ludum and the Corpus ludum starts making three hormones which include estrad a thing called inhibin but the most important hormone the one that you really need to know about is that it starts producing very high levels of progesterone progesterone levels start to increase about the time of ovulation although just prior to ovulation and over the next second half of the ovulatory cycle so about 14 days if it's a 28 day cycle a little bit longer a little bit shorter depending on the length of the cycle levels of progesterone in the second half of the ovulatory cycle are going to increase by 1,400 fold compared to what they were in the first half of the ovulatory cycle so again if we were to characterize the menstrual ovulatory cycle with in Broad Strokes what we would say is that FSH and estrogen Mark the initial part the first half so-called follicular phase and that the estrogen and FSH set in motion ovulation and they Prime the system for the production of a corpus ludum which produces progesterone and the second half of all of this is called the ludal phase the second half of the ovulatory menstrual cycle is the ludal phase because of Corpus ludum this otherwise discarded tissue that produces progesterone what does progesterone do well progesterone impacts the uterine lining so-called endometrium or the lining the mucus lining of the uterus where that egg that's ovulated is potentially going to implant if it's fertilized and so in a Kind of Perfect way or I should say in a um seemingly perfect way the egg is off on its way it might get fertilized the remnants of the compartment that let go of that egg produce a hormone that then prepares the endometrial lining of the uterus for the potential implant of that egg it's basically making the bed for the fertilized egg to potentially embed in to implant in and then achieve all the nourishment that it needs to grow eventually into a healthy embryo and child just an amazing set of biological mechanisms if you ask me because what you're observing here is an incredible economy of function whereby the same sell components that are producing the egg well some of them are being discarded but they're not being discarded without purpose they're being being discarded in a way that triggers the onset of hormonal expression that then prepares the fertilized egg to be in an enriched environment in which it can Thrive now I realized that was a lot of detail but we have a couple of key themes we've got the hypothalamus G&R we've got the pituitary with LH and FSH and those hormones travel to the ovary the ovary has eggs in a vault basically immature eggs in a vault some of those are activated by the presence of FSH and LH each month and and one of those eggs will be selected and will ovulate the remnants of the follicle and egg that are not selected the chromosomes that you don't need or disappear in the polar body and the Corpus ludum gives rise to Progesterone and sets in motion the second half of the ovulatory menstrual cycle which is the ludal phase which is essentially the potential for that fertilized egg to embed in a nice nourishing environment and of course we should all be thinking if the egg is fertilized and then it lays down in the nice comfy uterine mining that's been prepared by um progesterone in the Corpus ludum well then everything's fine and good but what if fertilization doesn't occur well we all know what happens if fertilization doesn't occur if fertilization does not occur for whatever reason that uterine lining is going to shed and that's actually what's referred to as the period it's the actual removal or the departure rather of the thickened endometrium lining of the uterus when fertilization has not occurred and of course if that happens we need another ovulatory menstrual cycle so how does that happen well the hormone inhibin is also made by the Corpus ludum and doesn't go quite as high as the hormone progesterone but it kind of tracks that increase in progesterone that occurs in the second half of the ovulatory cycle but then if fertilization does not occur inhibin levels start to drop and what I haven't told you is what inhibin does inhib IB in concert with other hormones like estrogen feed back to the hypothalamus and prevent the further release of follicle stimulating hormone and luteinizing hormone right if you have an egg that gets fertilized and can implant well then you don't want more eggs to mature right you want to hold on to the ones in the vault you don't want them to mature and hormones like inhibin and again working with other hormones are going to prevent the secretion of things like FSH and LH now typically people are not getting pregnant every month in fact that's not possible and part of the reason it's not possible is that if the fertilize egg in Plants there are a number of different hormone Cascades that shut down the production of things like G&R FSH and LH in ways that prevent further maturation of follicles in a follicular phase but in the instance where fertilization doesn't occur and menstration occurs and I should mention that that the duration of menstruation the actual bleeding typically is anywhere from 1 to 5 days the quote unquote heaviness the lightness or heaviness of that bleeding will depend on you guessed it the amount of progesterone that is secreted from the Corpus ludum that's one of the key players there and if menstration occurs well then inhibin levels also drop progesterone levels also drop and when that occurs there's a positive feedback signal up at the level of the pituitary the pituitary literally can register how much inhibit and progesterone and estrogen is present in the bloodstream and if those levels are sufficiently low well then GnRH gets secreted again FSH gets secreted again and LH gets secreted again and the first half the follicular phase of the menstrual cycle initiates all over again it's hard to overstate how beautifully orchestrated this entire system is the number of feedback loops and feed forward Loops I think if you can just generally understand that the first half of the menstrual ovulatory cycle is marked by the maturation of the follicles and FSH and that the second half is marked by the accumulation of progesterone and the thickening of the Uther in lining should fertilization and implantation occur I think that you will certainly understand the female reproductive cycle better than most people out there it will also help you understand a number of things that are sometimes associated with the female reproductive cycle for instance there are data showing that in many not all but in many women in the four to 5 days prior to ovulation there is a dramatic increase in libido that dramatic increase in libido is triggered by a number of things but some of those things include the spike in FSH that occurs the spike in LH that occurs and some Associated increases in androgens things like DHEA and testosterone which just as in males can be related to libido in females trigger libido you can imagine why this would be an effective mechanism to have in place in females if the goal as it were um certainly of the egg um perhaps not of the the woman as a whole but if the goal is to fertilize the egg so increases in libido just prior to the onset of ovulation there's also been a lot of discussion and interest and frankly data exploring the malays that can occur at certain portions of the of the menstrual cycle and there's a lot of misconception about this a lot of people have focused on the malays that can occur around the time of bleeding but there are actually stronger data to support the fact that some again some not all women experience a kind of Malay sometimes associated with anxiety sometimes not that's associated with the mid to second half of the ludal phase of the ovulatory menstrual cycle and that despite what people commonly think is not associated with elevated levels of estrogen it's actually associated with the depletion in estrogen levels that can occur during certain portions of that second half of the ludal phase of the menstrual cycle so um again this is highly variable um you know for some people they might not experience any malaise at any point during their menstrual cycle other individuals also for instance might not experience any variation in their libido at any point during their menstrual cycle again highly variable and yet there are some statistically significant trends that have been observed that track a very specific hormonal components within the menstrual cycle again this will all be very contextual and of course this can play out in a number of different ways so for instance some women experience very heightened levels of sensitivity to caffeine at certain portions of their menstrual cycle other women experience um more cramping than others uh different portions of their menstrual cycle tremendous variation from Individual to individual um one of the uh I view it as an advantage but one of the um things that many females can really do and experience because they have cycles that occur every month that are fairly dramatic in terms of the levels of hormone so for instance a more than thousandfold increase in progesterone during the lead ludal phase of the menstrual cycle and I should also mention a 200-fold increase in estrogen During the period just prior to ovulation that's why they always say estrogen primes progesterone that's a what you learn in kind of basic Endocrinology when you're learning the menstrual cycle estrogen in the first half of the menstrual cycle primes progesterone in the second half of the of the ovulatory menstrual cycle well that those estrogen increases just prior to ovulation are in part responsible for the increases in libido but it's also the presence of increased Androgen just prior to ovulation so there's a lot of complex interplay I think what we will do is we will reserve the discussion about libido per se and some of the other aspects related to sexual differentiation that we were talking about earlier for a future episode but hopefully now you have in mind what the ovulatory menstrual cycle is it is a signal from the brain from the hypothalamus which then a signal from the pituitary an endocrine gland which then signals the release of hormones that travel to the ovary and that control two things maturation of eggs and the identification of one egg in particular and then preparation of the milu the environment in which that fertilized egg could potentially land and mature into a healthy embryo and child so if you have that framed up in your mind and even if you just extracted maybe 10 to 15% % of the hormones and different aspects I described up until now I would consider you far more knowledgeable about this entire process than 99% of people out there certainly not the OBGYNs and urologists but than 99% of individuals out there it also frames up for us the second half of this whole story about fertility and fertilization which is the generation of sperm and how the sperm eventually arrive at the egg and how certain sperm are selected to potentially fertilize that egg whereas others never really stand a chance so next we're going to talk about sperm we're going to talk about what sperm are where they are generated and how they are generated and how they need to travel both within the male and within the female in order to allow fertilization to potentially occur I'd like to take a brief break and thank our sponsor insid tracker insid tracker is a personalized nutrition platform that analyzes data from your blood and DNA to help you better understand your body and help you reach your health goals I've long been a believer in getting regular blood work done for the simple reason that many of the factors that impact your immediate and long-term Health can only be analyzed from a quality blood test the problem with a lot of blood and DNA tests out there however is that you get data back about metabolic factors lipids and hormones and so forth but you don't know what to do with those data inside tracker solves that problem and makes it very easy for you to understand what sorts of nutritional behavioral maybe even supplementation based interventions you might want to take on in order to adjust the numbers of those metabolic factors hormones lipids and other things that impact your immediate and long-term Health to bring those numbers into the ranges that are appropriate and indeed optimal for you if you'd like to try insid tracker you can visit insid tracker.com huberman and get 20% off any of insid tracker's plans that's insidetracker docomond to get 20% off so we've covered the ovulatory cycle in females and I confess it was a lot of information with a lot of biological gnom in clure but I promise you that many of those same themes and indeed the same names in nomenclature will show up in the discussion that we're going to have now which is about the generation of sperm now sperm are similar to eggs in the sense that they are part of the germ line they are these protected cells protected in the sense that the activities of an individual are not going to change the genetic makeup of those cells now again there are instances in which mutagens such as chemicals could disrupt the genomes of The Germ cells in males just as it could in females but in general the activities the things that we do the experiences we have doesn't tend to change the Genome of those cells however there are a lot of Lifestyle factors do's and dones nutrition and supplements and prescription drugs Etc that can indeed modify the quality of the sperm and we'll talk about what sperm quality means but the point is that the sperm cell much like the egg cell are both germline cells they are not like somatic cells they are unique populations and let's just remember what the job of the sperm cell is the job of the sperm cell is to deliver the genetic material from the father and to do that in the form of a haid cell so that means 23 chromosomes 22 autosomes one so-called sex chromosome again not sex the verb at least not in this case sex the verb is a discussion we're going to have in a few minutes but sex the noun the sex chromosome can either be an X chromosome or a y chromosome okay so 22 autosomes and then one sex chromosome is going to be contained within the sperm because it's a haid cell not a diploid cell remember the egg was diploid then it became haid the sperm cells are cells that are created through the division of other cells but after that division occurs through a process called meiosis the sperm cell is going to contain 23 chromosomes consisting of 22 aosom and one sex chromosome and the sperm that manages to deposit its DNA contents into the egg to fertilize the egg will either have an XX chromosome or a yex chromosome and the yex chromosome has a number of different genes on that chromosome that will suppress for instance the development of the female reproductive axis one good example would be the mulian inhibiting hormone or mih the gene for mulian inhibiting hormone which is a hormone that prevents the formation of the mulian ducts which is part of the female reproductive structure well that Gene controls the prevention of the development of the female genitalia and in doing so promotes the development of the male genitalia and there are other examples of genes that are on the Y chromosome that give you a what we call male phenotype right you have genotype and phenotype by the way in case you haven't um heard this in a while from your high school biology or if you never heard it no big deal kot type is the complement of chromosome XX or XY and there are individuals out there that are xxy or XY y a discussion for our episode on sex differentiation that's karot type with a k then there's genotype which are the genes that you have and then there's phenotype spelled pH pheno p h n o t y p phenotype and the phenotype is how the genes which then code for RNA which code for protein how those are expressed in terms of things like eye color so eye color is a phenotype height is a phenotype hair color is a phenotype okay you have kype genotype and phenotype well what we need to do is we need to bring together that sperm which is haid contains those 23 chromosomal strands with either an X or a y sex chromosome is the 23rd chromosome we need to get that cell to the egg and so when we talk about spermatogenesis of course we're talking about the generation of sperm cells but what we're really talking about is the generation of cells whose job is to deliver the genetic material from dad to the egg within the female in a way that increases the probability that not only will that egg be fertilized but that it will progress in a healthy way with each set of chromosomes from Mom and from Dad each set of 23 chromosomes that is we progress in a healthy way we'll implant in a healthy way and will maintain and grow in a healthy way to a healthy embryo and child and eventually adult that's the job of the sperm okay so as we talk about spermatogenesis let's just remember that and why they're there in the first place now a few things about sperm that are interesting besides the fact that they're haid and besides the fact that as you all know they swim they have a head and a tail they actually have a head a mid region and a tail and that mid region turns out to be very important it's something we'll come back to again and again that mid region is really key for the ability for sperm to engage in forward W progression to swim forward um and involves the activity of mitochondria which are involved in generation of ATP which is involved in all aspects of energy in all cells but let's just remember that the sperm are swimming cells and in order to create a really good swimmer or set of swimmers you need a couple of things first of all within the testes is where the sperm developed and unlike in females and unlike in the ovary there's no Vault of sperm the sperm sperm are continually being generated it takes about 60 days for sperm to be born from their parent cells because cells actually give rise to other cells that's the way it works to be born from their parent cells and then mature to the point where they can be a really good swimmer now that doesn't mean that a bunch of sperm are made on day one and then 60 days later all those sperm are deployed in the form of ejaculate and then the cycle starts over again so it's a little different than the ovulatory menstrual cycle rather at any given point in time like right now if you have testes you have some sperm in your testes that are immature and cannot swim cannot deliver those contents uh to those genetic contents rather to the female egg and you have some sperm that mature and you very likely have some sperm that are so mature that they are dying off or that they're dead almost certainly also regardless of your age you have some sperm that are healthier than others are better swimmers than others this is just uh the way the system works now the process of spermatogenesis involves a couple of things but a lot of the players are the same as the process of developing the so-call oite the immature egg we've got G&R from the hypothalamus that's going to be a player we have FSH follicle stimulating hormone although the name's a little bit of a misnomer in the context of spermatogenesis because in the context of spermatogenesis there is no follicle what we're really talking about is FSH for stimulating the maturation of the sperm cell so not egg follicle but sperm cell but we still have GnRH FSH LH and rather than the ovary bring the target of those hormones it's going to be the testes so most everybody should know that the testes and the ovaries are the so-called gonads the testes of course reside outside of the body there are instances where the testes fail to descend during development certainly if the testes don't descend on time that's something that doctors need to be made aware of the the pediatrician to be made aware of because that can prevent fertility why would that be well turns out that the testes reside outside the body in the scrotum because the temperature conditions under which spermatogenesis can occur and under which healthy sperm can be maintained are very restricted and is approximately two degrees cooler than the rest of the body this is very important you know I think this is something that used to be discussed a lot more but isn't discussed so much these days but keeping the testes cool enough doesn't necessarily mean keeping them cold although there is a place for using cold exposure deliberate cold exposure to improve sperm quality and number and perhaps even testosterone levels we'll talk about that a little bit later but keeping the testes about two degrees cooler than the rest of the body is absolutely key if sperm get too hot they die and if spermatid the cells get that give rise to sperm get too warm well then often times the sperm that develop are not healthy not healthy in a number of ways either they can't engage in fastforward progression and SW that is swimming or they will lack the ability to deposit their DNA contents within the egg so again whatever is contained in the ejaculate is going to be a mixture of different sperm qualities and sperm of different ages will impact the quality but also the temperature under which those sperm developed is going to impact their quality and so we're going to get into tools a little bit later as I mentioned but just to give you a simple takeaway if you are hoping to conceive in the next 90 days right the spermatogenesis Cycle takes 60 days but then the sperm actually have to migrate from the testicle into the so-called epidemis which is a related structure and then into the vast defin and then into the urethra where it can be part of the ejaculate in order for sperm to do all that properly undergo that maturation and then exit ejaculate in a way that's healthy or that the sperm is healthy if you plan to conceive children or to try and conceive children in the next 90 days you definitely want to avoid exposing your testicles that is your scrotum to elevated temperatures so that means definitely avoiding hot tubs definitely avoiding hot baths now a brief hot bath or hot tub or hot shower isn't going to be a problem although if you're really interested in conceiving I would avoid hot tubs and and hot baths as much as possible hot showers are probably fine but if you're going to go into a sauna for instance you might want to rethink that decision and if you do decide to you almost certainly would want to bring a cold pack in that you could um well hopefully put some material between the cold pack and in the scrotum so you don't get a cold burn but put something there but keep the scrotal tissue cool keep it cold to cool because heat exposure can really mutate and disrupt the develop ing sperm and it can kill sperm and so again that would be for an entire 90 days leading up to your attempts to to conceive again we'll get into more tools later but a number of people also have probably heard of The Boxers versus briefs um controversy I guess it is um or whether or not uh people call it going commando with no um with no underwear of any kind boxers briefers briefs or otherwise rather turns out that the data on that point to the fact that there isn't really a big difference in terms of sperm quality if people wear boxers or briefs or don't wear anything under their um jeans or shorts at all um the scrotum has the ability to move the testicles far enough away from the body in order to achieve lower temperatures if it needs to it achieves that through a muscle called the creas muscle which is a really interesting muscle believe it or not I was reading up on the biology of the creas muscle something I never thought I'd spend too much time on but that I ended up spending far too much time uh reading up about and it's really fascinating what you have is a is a a muscle that's a smooth muscle tissue unlike skeletal muscle which is stried muscle that is temperature dependent so it has certain nerve endings and it has certain uh receptors on it that allow it to respond to local temperature and then to relax in order to um essentially let the testicles to descend further from the body or to contract and bring the testicles closer to the body in order to try and maintain the optimal temperature range and it turns out the creas muscle can achieve that whether or not people are wearing boxers or briefs although it stands to reason that any kind of um there's no other name for it undergarments you know I don't know why that word is is just seems kind of antiquated but undergarment that allows some movement of the of the scrotum and the testicles should be sufficient to allow these um temperature uh variations to occur and keep keep things in range um that said we a little bit later we'll go into some detail really because it's important as to why for instance if you are somebody who has big thighs believe it or not that it actually can lower sperm substantially whether or not the big thighs occur because you're very muscular the big thighs occur because you are overweight it can increase the temperature if you're sitting a lot increases scrotal temperature for sure and there are some other things that can increase scrotal temperature um seat heaters in cars for instance terrible idea if you just terrible idea if you're hoping to conceive in the near future um and again hot tub things of that sort okay so temperature modulation of spermatogenesis and sperm quality and function is key that relates a little bit more to tools but what happens how does the actual sperm develop well contained within the testical you have the cells the so-called spermatogonia which differentiate into so-called spermatocytes you don't have to remember all this and the spmat sites undergo this process of meiosis meiosis is a form of cell division which reduces the chromosome number to those 23 individual strands as opposed to pairs right so it makes them haid as opposed to diploid very very important for reason that we talked about earlier and the meiosis process in these primordial sperm cells these immature sperm cells is similar to the meiosis process that occurs in eggs when the chromosomes segregate and that involves these spindle like um structures within the cell now why do I keep bringing up the spindles well it turns out that the function of the spindle in the egg in the sperm is heavily dependent on mitochondrial function and later when we get into tools for improving egg and sperm quality you're going to hear about a lot of tools for improving mitochondria and it's not just because the mitochondria are involved in in energy demanding aspects of Cell Biology but it's also because the mitochondria in this context are very very important for the removal of or the separation of one set of chromosomes to give you these two sets of haid cells the egg and the sperm and this is so important because many failures at fertilization many failures at implantation many many miscarriages and many birth defects that do survive after birth that are very detrimental such as trimes and things like that occur because the spindles don't effectively pull apart the chromosomes in the typically the egg but it can also occur in the sperm okay so these spindles and the fact that mitochondria are rich on the spindle are very important for generating these haid sperm again 23 individual strands of chromosomes that's occurring inside of the testes okay so there's not as much long distance migration of the sperm of the spermatocytes and the sperm cells as there is the egg just when you think about the overall architecture of the uterus and the Fallopian tubes compared to the testicles but there's still a lot of movement So within the testicle if you were to look at the testicle in cross-section and I prefer to call it that rather than cut the testicle in half anytime you talk about Anatomy you actually talk about slicing things that's what you would do with a kadaver is what um I teach and we do um my laboratory and frankly in biological Laboratories all over the place but when you talk you to talk about if you were to take a visual cross-section through the testicle what you would find is that there are a lot of different little tubes a lot of ducks du C TS Ducks those are Pathways and the main ducks that are important for this discussion are called the seminiferous tubules okay so it's a it's a A meshlike or network structure of tubes in the testicle and the immature sperm sit on a little compartment um along the edge of those tubes and as they mature they move towards the center of those tubes and then when they are mature enough those sperm cells actually drop into the hollow of the tube and then can travel through those tubes to a structure that's along the side of the testicle called the epidemis the epidemis again is a series of ducks and then the epidemis converges with something called the vast Defence okay I think in high school we all remember this by thinking about it's the vast difference I don't know that I don't know who came up with that maybe I think it was a a young girl sitting to the left of me that was like oh it's like the vast difference I never forgot that I don't know maybe it was a topic matter maybe it was her maybe it was some combination of the two but in any case the sperm go from the seminiferous tubules to the epidemis and then to the vast defin and then are contained in the ejaculate along with seminal fluid now the seminal fluid is the carrier fluid for the sperm themselves this is important because it turns out that a lot of things that can both negatively or positively impact the quality of the sperm relates not just to the sperm cells themselves and the temperature of the environment that they were uh matured in but also to the seamen quality for instance if you are a heavy drinker if you are a smoker or if you are a regular user of cannabis especially if you smoke cannabis or or vape cannabis you create a lot of reactive oxygen species that disrupt the chemistry of the seminal fluid which disrupts the sperm cell so it's not a direct action always on the sperm cell itself although it can be so for instance in the form of of smoked tobacco or cannabis there are a lot of carcinogens and mutagens that actually mutate the DNA can cause DNA fragmentation and debilitate sperm but there are also a lot of things created by smoking in particular whether regardless of what's being smoked that can create elevated reactive oxygen species and dis disrupt the seminal fluid that the sperm are contained in in the so-called ejaculate the seamen now this will also become a relevant conversation later when we briefly talk about vasectomies vasectomies are literally a cutting of the vast defin which leads to a situation provided the surgery was done correctly where men can still achieve all the other aspects of intercourse they can still uh achieve erection they can still achieve orgas they can still ejaculate but when they ejaculate the seol fluid is released but there are no sperm contained within the seminol fluid and it turns out that um vasectomies are a very effective form of birth control and they always check to see if zero sperm and confirm that zero sperm are being released in the ejaculate they are reversible that is vasectomies are reversible but not always there are a subset of cases where it's not reversible in which case if people still want to have children you have to go in and actually surgically extract sperm from the testicles but it's a process in which the vast defin is altered or severed in a way that the sperm can't actually exit the testicle they can get into the epidemis usually but not into the vast deference and so on and so forth um so if you've ever wondered what a vasectomy is that's what a vasectomy is and I mention vasectomy now because it illustrates the difference between the seminal fluid the semen and the sperm that the seen contain Okay so so 60 days to generate these the sperm another um 2 weeks or so for the sperm to travel through the various ducks to the point where they can be contained in the ejaculate let's talk about the sperm cells themselves the sperm cells again have these 23 pairs of of single strand chromosomes they're haid they have either an X or a y sex chromosome as the 23rd so-called sex chromosome and as we all know they have a head that head tends to be oval in most cases that head contains very important enzymes and proteins that are designed to fuse with the much larger egg and to actually take the membrane of the sperm cell and combine to actually mesh with the egg cells membrane and then deliver the genetic contents to the egg cell in other words to fertilize the egg cell now just behind the head is a region called the mid region that mid region is a slightly thickened region and here of course I'm talking about healthy sperm cell morphology morphology simply means shape a mid region that mid region has a bunch of things related to cell motility and to the forward progression of the cells first of all it is choa block full of mitochondria in fact if you were to look just behind the head of the of the sperm what you'd see is that it is completely surrounded by mitochondria there are mitochondria elsewhere in the cell but most of them are contained in this mid- region compartment just behind the head of the sperm and that thick region is where the tail movement of the sperm the um the flagellation back and forth is actually generated from much like if you were to hold a rope you know like a battle rope in the gym um and you were to uh you know whip the battle rope the whip at the one end of the Rope is what allows for the um the sort let's just call it what it is that the Curves in the rope that the oscill ations the rising and falling of of the robe all the way out to the end right it is the force of the of the whip right at that end that you're you know with a battle rope you're doing with your hand and with a sperm that is occurring just behind the head of the sperm that is actually going to dictate how fast and how well that sperm can swim and indeed the sperm has to swim very far how far well on a relative scale and again these are estimations because they're going to be uh how should we say there will be differences in the distance from the head of the penis and where the ejaculation occurs to the cervix depending on the relative size of the vaginal canal and the penis that delivers the ejaculate to the vaginal Canal but once the sperm arrive at the cervix okay which is at the back of the vaginal Canal just at the opening to the uterus once the sperm arve there the distance from the cervix to the Egg of course will vary depending on where that egg is in its ovulatory trajectory its pathway but it is Ain based if you scale for size to the distance between Los Angeles and San Francisco which is many many hundreds of miles so those sperm have to swim very far now of course if the sperm are delivered in the vaginal Canal somewhat further away they will have further to go if they're delivered right at the cervical opening they will have less far to go the very effective swimming sperm swim very fast so they are able to accomplish that distance in just a few days and this relates to a discussion that we will get into in a lot more detail later as to how often couples should have intercourse if they're trying to conceive many people might think well it's every day however the more frequent the ejaculation the lower the concentration of sperm in each ejaculate so this is not a discussion about how often to have intercourse depending to your preferences for pleasure or bonding or whatever reason this is a discussion about how often to have intercourse in order to optimize the probability of fertilization of the egg there's some general rules that of course come to mind which is ejaculations close to ovulation both before during or sometimes after are obviously advantageous but you will also hear OBGYN and urologist suggesting intercourse every other day leading up to the day of ovulation start starting about 3 to 4 days out from the day of ovulation so we got a little bit sidetracked albeit I think appropriately so and focusing on fertilization but what we were talking about right up until the point of that is the anatomy of the sperm itself which is the head the mid region that contains all those mitochondria and then the tail now what we haven't discussed is the actual generation of the sperm so if you're a male or if you're a female I think it's really important to understand how spermatogenesis Works spermatogenesis Works in much in the same way that the generation and maturation of eggs work although as I mentioned before it's going to occur ongoing throughout the cycle of the male's life after puberty we already talked about puberty and I'll just cover this in two or three sentences as it relates to males and it's essentially the same thing the hypothalamus up until the point of pubert is providing suppression of the release of genotropin releasing hormone then some biological clock which is still not clearly understood it's probably not leptin coming from body fat again unlike in the female it's probably not leptin coming from body fat but some other signal arrives to the hypothalamus removes that inhibition and G&R ganat tropin releasing hormone is now released onto the pituitary a bunch of hormones are deployed from the pituitary as a consequence the two most important ones for the context of this discussion are follicle stimulating hormone and luteinizing hormone follicle stimulating hormone and luteinizing hormone travel to the testes and they're going to do two main things one they're going to trigger the production of testosterone and they're going to trigger the production of the sperm themselves they're going to set in motion for essentially the rest of the life of the male the production of sperm they're going to initiate the spermatogenesis cycle and that cycle is going to be ongoing at various stages for different sperm for the rest of the man's life this is very different than the triggering of development of oyes and eggs in females where there's an existing Vault that Vault can be depleted to the point of zero where it can't occur again men can generate sperm their entire lifetime of course there's a diminishment of sperm production in very very late age say 80s and 90s or hundreds but believe it or not there's still sperm being produced the quality of those sperm is another question so everything we're going to talk about now is essentially puberty onward okay prior to that testicles are present but they're not generating sperm ejaculation isn't possible or if it is possible it's very unlikely and unusual and it's not going to contain sperm everything we're going to talk about now is puberty forward okay so puberty onward to the rest of life and luteinizing hormone secreted from the pituitary acts on the testes and on a very specific cell type in the testes called the litig cells or leig cells l y d the ladig cells the ladig cells of the testes are what produce testosterone testosterone is going to have two major effects and here I re mean really major because it has many many hundreds of effects on different tissues of the body in fact that's the definition of a hormone really it's a it's a substance that acts in an endocrine fashion it can act on the very tissue that generated it so for instance testosterone made by the lighting cells within the testes will act on the testes as we'll talk about in a moment but it can also act on other tissues it can act on the fering and larynx and deepen the voice as it does during puberty it can act on the hair follicles and generate facial hair it can act on the musculature and generate protein synthesis and development of muscle bone Etc okay all the things we associate with puberty and with testosterone typically restricting the conversation to the effects of testosterone on the testicle itself and on spermatogenesis the LI Exel make testosterone and keep in mind that some of that testosterone will travel elsewhere in the body and do its thing for gene expression and the more accute effects of testosterone on the brain included but the testosterone within the testes is at extremely high concentration in fact the concentration of intratesticular testosterone is at least a 100 times higher than the concentration of testosterone anywhere else in the body even though it's being secreted into the rest of the body and that's because there a number of different so-called binding proteins and enzymes that sequester the testosterone within the testes so the liic cells are making testosterone a lot of that testosterone is acting on and is restricted to the testes and that turns out to be very important because testosterone within the testes acts in concert with a different biological program that starts with FSH follicle stimulating hormone that also travels to the testes and acts on a very specific set of of cells that are called supporting cells or more specifically the ceroli cells the CI cells are the cells that generate something called ABP or Androgen binding protein and it is the combination of testosterone from the liting cells an ABP from the CI cells that is necessary for spermatogenesis it's necessary for those spermatocytes to become what will eventually be healthy mature sperm that have really nice shaped oval heads have a mid region choa block through mitochondria and can generate a fast whipping motion of the tail to swim from the cervix or up the vagina to the cervix and from the cervix to the egg to fertilize the egg so it's really a basic set of chemical players that are involved here and so basic in fact that if you were to disrupt any one of these chemical players either the luteinizing hormone the FSH the testosterone from the litic cells or Androgen binding protein you would observe pretty marked disruption in spermatogenesis or the elimination of sperm entirely we'll get into a few deficits in sperm development and sperm number and sperm function a little bit later but just keep in mind or I should say maybe sit back and just appreciate that the exact same players G&R from the hypothalamus which causes luteinizing hormone and follicle stimulated hormone release from the pituitary which travels to the gonad which in this case is the testicle which triggers the release of testosterone from lieg cells which triggers the action of the supporting cells the CI cells which make Androgen binding protein testosterone and androgen binding protein combine and create a chemical and actually a structural milu in which those little spermatocytes can go from the walls from literally the walls of the tubes of those seminiferous tubules can mature into healthy well-developed sperm and can hop into those Ducks those little tubes and then head off to the epidemis where they will reside the epidemis is the tissue nearby the testicle or surrounding one portion of the testicle and then eventually fused with the vast defin can combine with or be contained with rather the seminal fluid and then can be ejaculated via the urethra into the female where then they can swim very quickly effectively the distance for them anyway from Los Angeles to San Francisco over the course of a very short period of time and fertilize the egg so that's the process of spermatogenesis the maturation of sperm which is ongoing throughout the lifespan from puberty onward and in doing so we talked about some of the hormonal elements coming from the hypothalamus and coming from the pituitary and within the testes themselves the leig cells which produce testosterone the CI cells which are the support cells that allow spermatogenesis to occur with that in mind next I'd like to think about what's actually contained in the ejaculate in terms of numbers of sperm and what's really being selected for in terms of the sperm that actually successfully fertilizes the egg and what sorts of elements come into play in dictating whether or not fertilization will or won't occur and the major themes that we're going to discuss are frequency of ejaculation but really that's just kind of a proxy for talking about maximizing sperm concentration and quality of sperm arriving at the egg right because remember ovulation in the menstrual cycle are really about creating the opportunity for fertilization okay and we are also going to talk about how the vaginal duct the vagina and the milu around the cervix and some other elements within the female herself contribute to and support the sperm in their Journey to the egg and in the likelihood that they will fertilize the egg so really what we need to talk about first is sperm quality and we should also probably talk about ejaculate quality because as odd as that theme might seam really the ejaculate quality which has a number of different parameters including the number of mature sperm that are not so mature that they're swimming slower or dead but also quality sperm that have for instance one tail it's not entirely uncommon to see sperm with two tails right because they just didn't form properly or sperm that are not moving very much um in fact sperm motility is scored along a scale of 0 1 2 or three three being the best forward fast forward progressing a zero is moving at all um one they're actually called twitchers right twitchers are sperm that sort just Twitch in place but don't undergo forward progression two is somewhere in between uh one and three not surprisingly different clinics different OBGYNs different urologists will throw out different numbers but in general it is hoped that more than 50% of the sperm should be motile in some way or another so not scoring a zero but a one a two or ideally a three the concentration of sperm of course if it's higher within the ejaculate you know the total number of sperm per milliliter of ejaculate if that's higher then there's a higher probability that one of those sperm will fertilize the egg one thing I didn't mention before when discussing the production of eggs in ovulation and I probably should have so I will now is that most often only one ovary gives rise to an ovulating egg right it's it happens but it's some somewhat rare for two mature eggs one from each ovary to be deployed during a single ovulation uh there's a name for that when it occurs and both are fertilized it's called fraternal twins um if a single egg that of course comes from a single ovary is fertilized and the Egg splits and that's something that happens further along the process of fertilization and differentiation of the embryo well then what you get are identical twins okay um are other instances that are um quite uncommon in which you can get fraternal twins through other circumstances but in general that's the way it works but essentially what happens is one egg from one ovary that's the most common occurrence the sperm once ejaculate into the vaginal duct are going to pass through the cervix and then are going to swim toward the egg the egg could be at varying locations along the female reproductive axis now this is actually a very important thing and actually gets right down to um the safety of both the potentially developing embryo and the mother there is something I referred to as ectopic pregnancy and that's when the pregnancy actually occurs within the Fallopian tubes so the precise location in which fertilization between the sperm and the Egg occurs can vary somewhat but ideally the fertilized egg implants into the endometrium or the endometrial lining of the uterus and develops there as opposed to within the Fallopian tubes which is so-called ectopic pregnancy now where they spr sperm and the Egg meat exactly can vary as I mentioned before but in general the faster swimming sperm and the more far along the ovulatory trajectory the egg are the higher the probability of a successful fertilization because of the proximity to the implantation zone of the uterus so basically it's all a probabilities game it's a probabilities game related to the number of sperm cells that encounter the egg and where the egg is in terms of its ovulatory cycle and also its position where it is in the ovulatory cycle the sperm parameters I should say the seen parameters and ejaculate parameters that most clinicians want to see if you were to give a sperm sample would be somewhere in excess of 15 million sperm per milliliter of ejaculate now there's a lot of discussion nowadays it seems to be a very popular news theme to talk about diminishing sperm counts you know the idea that 100 years ago or maybe even 35 years ago go the typical male ejaculate contained 100 million sperm per milliliter and nowadays it's down to 15 to 20 or 50 and indeed sperm counts do seem to be declining and the exact reasons for that are not clear now I confess I'm a little bit reluctant to talk about this because um there have been a lot of back and forth discussions about the safety of emfs of electromagnetic fields that's not exactly what we're talking about here but there are some excellent data contained in metaanalysis and reviews that I will provide links to and that we'll talk about in more detail in a minute that correlate the Advent of smartphones and in particular carrying of smartphones in the pocket with diminishing sperm counts although there are certain to be other factors that can explain diminishing sperm counts as well um Dr Shaina Swan uh for instance has done beautiful work describing how the phalates um and the bpas and so-called end endocrine disruptors might be disrupting some of the milu of the seminiferous tubules so this would be reductions inest testosterone Endor disruptions to the ctoi cells and endogen binding protein brought about by endocrine disruptors such as phalates contained in pesticides and contained on printed receipts and things of that sort there are some data that that is negatively impacting um sperm counts how much so is still debatable there are also quite good data pointing to the fact that both the heat related and the non-heat related impact of smartphones and laptops contained on the the lap are impacting sperm cent in a negative way again there's going to be tremendous variation in the concentration of sperm for one individual to the next it will vary according to age and a number of other factors that we'll talk about a little bit later but in general if somebody is wishing to conceive then clinicians like to see a ejaculate volume of more than 2 milliliters so jaculate volume can be anywhere from 1.5 to 5 millit and that will strong strongly be determined by how frequent ejaculation is occurring there's a lot that goes into evaluating the quality of ejaculate in sperm but basically these huge variations that are observed of anywhere from 15 million sperm per milliliter or in some males who are not producing sperm for whatever reason we'll talk about those reasons in a little bit the uh as low as 5 million uh sperm per milliliter all the way up to 100 or maybe even 200 million sperm per milliliter huge variation the cause of which is not always clear but is certainly determined in part by the frequency of ejaculation so because there are so many variables impacting why one male versus another male or even the same male across the lifespan might have variations in his uh concentration of sperm within the ejaculate let's talk for a second about frequency of ejaculation as it relates to the goal of fertility per se because that's really what today's episode is all about so what I'd like to talk about next is how people can increase the probability of a successful fertilization focusing both on the components from the male side and from the female side and I'm mainly going to couch this discussion in the context of the so-called natural method of sexual intercourse and ejaculation in Vivo right within the female but I will also touch on some parallel themes as it relates to invitro fertilization and intrauterine insemination okay so the idea here is that we want the maximum number of highquality sperm that is rapidly forward motile sperm that are of the correct morphology that is shape that's going to require a lot of mitochondria in the mid region a well-shaped head so it's going to be an oval-shaped head the tail is going to be a single tail not multiple Tails these aren't going to be the twitcher type of of uh or immotile type of sperm that are either twitching in place or aren't moving forward all of those components are going to be essential for increasing the probability of fertilization but of course there's the female side of it too which is that ovulation occurs on just one day during the menstrual ovulatory cycle and that egg will be available for fertilization for approximately 24 hours now keep in mind that the sperm can survive within the vaginal duct and within the area around the cervix and within the uterus and along the female reproductive tract for anywhere from 3 to 5 or it's even been described as up to 7 days but generally it's going to be about 3 to 5 days now most women can figure out the day of their ovulation by counting the total number of days of their typical cycle and this is where it's really useful to have a cycle that's of more or less regular duration or rather of more or less regular length so as we talked about earlier if somebody's cycle is 21 days or 25 days and it's 21 or 25 days consistently or even 30 days consistently that's going to be a far better scenario to favor fertilization then if it's 20 days one month and then 21 days the next month but then suddenly you know 30 days and then suddenly 35 days those varying durations of the ovulatory cycle make it very hard obviously to time and understand when ovulation is going to occur so regular duration ovulatory Cycles are the ideal circumstance and they're the ideal circumstance because even though the egg is only available for fertilization for a few days those sperm can survive for some period of time which leads to the issue of how often should couples be having intercourse and here I'm referring specifically to intercourse with ejaculation how often should couples be having intercourse around the time of ovulation if the specific goal is successful fertilization of the egg and the creation of a baby okay this is leaving aside all issues which of course are interesting issues related to how often people are having intercourse whether or not there's ejaculation every time they have intercourse or not for sake of pleasure or sake of pair bonding and pleasure or for sake of any number of other potential goals of intercourse here I'm only referring to intercourse as it relates to the goal of fertilization of the egg okay so knowing what we know about spermatogenesis and the fact that ejaculate is going to contain a certain concentration of sperm but that within that ejaculate some of the sperm will be older and less healthy and some will be optimally mature and some might even be a little bit immature although there's a tendency for the immature sperm to not have yet exited the sem ious tubules um gone into the epidemis and vast deference but given that the ejaculate contains sperm of varying ages and therefore varying quality and given that with each successive ejaculation in a short period of time there's going to be a decrease in the concentration of sperm per milliliter of semen of ejaculate we can make some good arguments as to how often couples should have intercourse with ejaculation around the time of ovulation if the goal is to fur ize if ovulation occurs on for instance day 14 of a cycle and here we're using the kind of standard average of 28 days of the cycle but for some people with a 30-day cycle you know that could be uh day 15 or um with a shorter cycle it could be day 12 for instance but given a 28 day average cycle let's say ovulation occurs on day 13 or on day 14 and typically would occur on day 14 of a 28 day cycle well then given how long sperm can survive inside of the woman you might think that the optimal strategy would be to have as much intercourse with ejaculation in the 3 or 4 days leading up to ovulation hope that those sperm swim as far as they possibly can and will encounter the egg just as soon as possible after it ovulates turns out that's not the optimal strategy the optimal strategy is really to maximize the concentration of healthy sperm within each ejaculate and to really Center that around the day of ovulation so what this involves generally and with the typical recommendation is is to abstain from intercourse with ejaculation about two or three days out from ovulation and then on the day prior to ovulation and on the day of ovulation to essentially introduce as much semen and ejaculate into the reproductive pathway of the female as possible okay now that's the general recommendation that the OBGYNs and the urologists that I spoke to gave but you will also here a different strategy it's only slightly different but the different strategy involves trying to maximize the concentration of healthy sperm within each ejaculate with the understanding that with each subsequent ejaculation over about a 24-hour period that there's going to be a dramatic reduction in the concentration of sperm what that means is that if a couple for instance were to have intercourse with ejaculation many times on the day prior to ovulation yes that will introduce a lot of sperm into the reproductive pathway of the female but what it means is that on the day of ovulation if they were to have intercourse the number of highquality sperm that will be available to the egg will be greatly diminished and if none of the sperm that were introduced in the day prior managed to fertilize that egg well then essentially chances are off that there will be fertilization or they're greatly diminished rather if they're having intercourse with ejaculation once or twice on the day prior to ovulation and then a maximal number of times with ejaculation on the day of ovulation that itself can maximize the probability of fertilization so which strategy is optimal should couples have as much intercourse with ejaculation on the day prior to ovulation and on the day of ovulation or should they have intercourse on the day prior to ovulation but not so frequently that it diminishes the concentration of sperm and then allows for intercourse with the maximum number of ejaculations on the day of ovulation you really hear it both ways and what this really boils down to is frankly that nobody knows and the reason nobody knows is that there's tremendous variation among males in terms of the absolute concentration of sperm per milliliter of ejaculate and the amount of sperm per Mill of ejaculate within a given time frame but what everyone agrees on is that a period of abstinence ranging from 48 to 72 hours prior to an ejaculation increases the concentration of highquality spr within that first ejaculation to occur after the abstinence period okay so again to reiterate if one's goal is to fertilize the egg you want to take into consideration that most often there is going to be a dramatic decline in the concentration of sperm per ejaculate anytime those ejaculations are occurring within a short period of time say within 12 to 24 hours of one another now all of this of course also relates to the female biology and the extent to which the woman can precisely identify the day and timing of her ovulation some women feel as if and indeed are very accurate at estimating their time of ovulation to within a couple of hours or some women even report being able to feel their actual ovulation whether or not they are feeling the ovulation itself the you know the deployment of the egg or not isn't clear I certainly would know I've I've never produced eggs nor have I ovulated um and I'm certainly not going to contest the idea that women um can do that I mean it makes sense that some people have a very um Keen so-called interoceptive awareness and awareness of the sensory events within their body and while of course the ovaries are not thought of as an organ that we want to be able to sense what's going on in there in terms of feel there are sensory endings within the ovary and so the notion that one could literally sense changes within their ovary including the deployment of the egg is not um outside um the bounds of reason and in fact could likely be the case now that said there are a number of different ways that women will track their ovulation one is the temperature method so they'll actually measure intravaginal temperature um they're looking for changes in temperature that are consistent around the time of ovulation we're going to have an expert guest on in OBGYN who can tell us a lot more about the details and nuances of the temperature method you'll see a lot of information about this online but there's a lot of misunderstanding about it as well other women will use apps that take into account either the temperature information if they're acquiring temperature information that'll be entered into the app as well as marking the onset of menstration the onset of bleeding therefore the start of the ovulatory cycle because of course as we mentioned earlier that marks day one of their cycle and then again and again you can see how regularity of cycle duration or relative regularity of cycle duration really favors this whole process of being able to predict when one ovulates and fortunately if the goal is fertilization there are some margins for eror that are introduced by the fact that the sperm can survive within the female reproductive tract for some period of days thereby reducing the need for absolute certainty about the time of ovulation and so on in fact it's pretty well known that around the time of ovulation a couple of things happen earlier we talked about one thing which is there's an increase in libido just prior to ovulation this relates to in part an increase in some of the androgens things like DHEA but also testosterone and some related androgens that can increase libido both in males and females and changes to the reproductive pathway of the female in particular a change in the pH that is the relative acidity versus basic nature of the mucosal lining near the cervix and also vaginal secretions such that around the time of ovulation the entire milu of the vagina and the cervix and the locations in which fertilization can occur and certainly in which the sperm are swimming towards the opportunity for fertilization is shifted to support sperm motility and health in other words the one of the best environments for sperm to survive is going to be within the female reproductive pathway itself and as long as we're talking about vaginal secretions and mucus it's important to point out that a number of commercially available lubricants can actually be detrimental for sperm Health even if they don't contain spermatid so this is something that you'll want to discuss with your OBGYN or certainly if you're male you could also discuss this with your urologists and your partners OBGYN a lot of the commercially available lubricants contain chemicals that while they may favorably change the consistency or the viscosity of the vaginal pathway for purposes of intercourse certainly may not be the most favorable for maintaining the health of the sperm and the motility of the sperm so again here we're talking about intercourse only in the context of trying to maximize fertilization and I should mention that there are certain lubricants that are more conducive to the sperm environment but it's something that you'll really want to talk your OBGYN about or at least read up about if your interest is in trying to fertilize and develop an embryo so we covered the optimal strategies for how often couples should have intercourse with ejaculation around the time of ovulation in order to maximize the probability that successful fertilization and ultimately pregnancy will occur what we haven't covered yet however is how long couples should apply that method over time in order to achieve successful fertilization and pregnancy now of course if a couple decides that they want to conceive and they apply that method or any other method for instance and they achieve fertilization and a successful pregnancy the very first month that they try well then there's no other work to do at least until that child is born and if and only if they decide they want have more children however many couples find that they do not conceive in the first month of trying even when they apply the optimal methods and even if their age and every other Factor related to egg quality and sperm quality is optimized now I think it's the rare instance in which egg quality and sperm quality are optimized in fact the word optimal and optimization and optimized is a little bit misleading in general because no one really knows what that is but of course there is an ideal there's a perfect standard to which everyone would like to achieve but of course we all enter the picture with genetic variables environmental variables and so forth many of which we'll talk about because you can in fact adjust them in the direction that you would like to improve sperm and egg quality but most people simply will not succeed in achieving a successful fertilization the first month that they try now there is a truth that governs how many tries it ought to take in order to achieve successful fertilization and ultimately pregnancy and it's very age dependent and in particular it's dependent on the age of the mother because the age and quality of the egg while it's not the only factor is certainly one of the most determining factors in whether or not successful fertilization occurs and as women age the quality of the eggs tends to diminish over time largely due to changes in the mitochondrial function and the spindle that pulls the chromosomes apart although there could be other factors involved as well now before continuing any further I just want acknowledge that this whole language around egg quality and sperm quality is not the greatest language because it's entirely subjective and yet the word quality in these instances is really there to explain a broad variety of factors that can in fact be measured things like the number of follicles that are deployed each month in a woman's ovulation or the number of motile sperm or the number of morphologically that is correctly shaped sperm in the male and so forth so when we talk about egg quality or sperm quality we really refer to an amalgam of different features related to the different aspects of ovulation leading to successful fertilization or the different aspects of sperm related to whether or not they can arrive and deliver their DNA contents and so forth so I will use the words egg quality and sperm quality just as general themes because that's what a lot of the clinicians use but I do understand that it's a little bit of a loaded term in both instances and it doesn't relate to any one specific parameter per se so getting back to this issue of how long couple should try according to the age of the female and perhaps also the age of the male well most of the data that have been collected relate to the age of the femal as I mentioned before and what we're about to discuss is within the scientific literature described as what's called fundability which is the amount of time over which a given couple needs to attempt to conceive of course by having intercourse with ejaculation around the time of ovulation okay it assumes that all the other things are being done correctly and what we know is that there's a strong age dependent effect that largely rests on the age of the egg that is of the female and what we know is that for females 30 years old or younger if they have intercourse with ejaculation around the time of ovulation say on the day before and on the day of ovulation and there could be other intercourse with ejaculation around that time as well on average that will result in a successful Fertilization in preg about 20% of the time on the first month of attempting the first ovulation cycle now if Fertilization in pregnancy occurs great right there'll be at least a 9-month lag until they decide whether or not they want to try and conceive again however most couples even if the woman is 30 years old or younger will not successfully conceive on that first attempt and that's because the probability is not 100% it's 20% so 80% of the time they simply will not conceive which means that they hopefully will try again the very next month and if they successfully conceive great and if they don't then they ought to try again the next month the next month and so forth now the typical advice that an OBGYN would give you is that for a woman 30 years or younger and leaving aside the age of the father but still assuming that egg quality and sperm quality are sufficiently high to achieve fertilization that the couple should or if the woman's trying to have kids alone the woman should attempt to conceive over the period of 6 months why well if you think about it if there's a 20% chance in the first month and it's unsuccessful well then on the second month there'll also be a 20% chance on the third month also a 20% chance what I'm describing here is what obviously is independent probabilities that is if you were to flip a coin and the probability of getting heads is 50% the probability of getting tails is 50% of course you don't expect that the previous flip had anything to do with the result that you'll get on the subsequent flip that's what independent probabilities are however when it comes to fundability we were really talking about something which is called cumulative pregnancy rate which is not really independent probabilities now why would that be why would it be that if you did not successfully conceive in the first month of trying that by simply trying again and again and again the probability of conceiving would increase well the reason for that is that this whole business of fertilization is not just to about what's happening with the egg it's also about what's happening with the sperm so there are a number of different events related to the biology of the egg and the biology of the sperm which you are now very familiar with from everything I've talked about up until now and there are a bunch of chance events for instance that the sperm won't actually arrive at the egg in time or that the egg won't arrive at the sperm in time because of course it's a bidirectional migration of those two cell types or that for whatever reason fertilization won't occur so what we're really talking about when we talk about the cumulative pregnancy rate over time is the fact that there are multiple probabilities at work and yes those are somewhat independent in the sense that the biology of the sperm doesn't really strictly depend on the biology of the egg at least not until they meet and fertilize but the likelihood of pregnancy depends on those independent probabilities which makes this a cumulative pregnancy rate now if any of that is confusing what it basically means is that for the egg in the sperm to meet and to fertilize a number of different events that carry some intentionality right the sperm swims towards the egg and so forth the egg we doesn't have a a personality in there at least not yet but it quote unquote wants to be fertiliz right it is in principle receptive to fertilization well in order for that to happen there are going to be some events related to chance that could limit the ability for that to happen and there will be other events dictated by the biology of those two cell types that are driving that event to happen that are biasing the event to yes happen and so what we're talking about when we talk about cumulative pregnancy rate is how much of the biology of the woman is skewed towards fertilization to be likely to occur okay so to make this very simple all we need to know is that for women 30 years old or younger because the probability of getting pregnant on any one attempt to conceive is 20% well then if that doesn't occur the first time then she should simply repeat that at least five and probably six times before deciding to go to an OBGYN and conclude that the something going on either with the egg or of course it could be with the sperm okay because 20 * 5 is 100 so we're talking about cumulative percent so 20 40 60 80 100 and the six month there would take you to 120% um which is a different thing altogether but in general that's why OBGYNs will tell their female patients look if you're setting out to conceive try for about five or six months and if you're not successful come back and see me now for women who are age 31 to 33 the probability of conceiving in that first month drops to about 18% so women in that age range and their Partners should certainly try and conceive naturally over a period of 6 or S months in order to get to that 100% cumulative probability and then for women who are age 34 to 37 the probability of conceiving in that first month of a of trying and certainly every month thereafter is about 11% so when the age of the woman starts extending out to about 34 or 35 years old then the typical advice of the OBGYN is is going to be to attempt to conceive over a period of about 9 months to a year before deciding to take some sort of medical intervention and then of course as the age of the woman increases so too does the quality of the eggs go down now that's not true for every women there are many women who in their late 30s and 40s and even early 50s have successfully conceived healthy children although the probability of that the likelihood of it drops substantially so for instance for women who are aged 38 to 39 the probability of a successful conception by natural conception intercourse with ejaculation is going to be about 5% right so it's really dropped to a quarter of what it was when that woman was 30 again these are averages only what does that mean well it means that if you are age 38 or older chances are that you should probably go to your OBGYN right at the outset of your desire to conceive and ask what you can do to improve egg quality otherwise if you were to extend the math out right we know that if you're age 30 or younger 20% chance in any one given month that means about four to 6 months of trying well you can simply multiply that times four or five for someone in their late 30s or early 40s and so what you're really talking about is several years of trying and of course what's happening during those several years the woman is getting older and as a consequence the quality of the eggs is declining even further so if you are you know 35 36 years old it might not be entirely unreasonable to talk to your OBG why in right at the outset of Desiring to conceive but you could also just take the approach of trying to conceive naturally for about a year or a year and a half before deciding to do that keeping in mind that all the while you can't stop time so biological time and aging is going to occur in the backdrop but hopefully this description of cumulative uh pregnancy rate makes sense again the idea is that while it's true that every single month there's an independent chance of the woman getting pregnant and that chance is dropping from about 20% at age 30 over time to about really 1 to 3% for women 40 or older there's also this notion of cumulative probability which involves multiple biological events in both the egg and the sperm that have to converge in time and space in order for successful fertilization to occur now as long as we're on this topic I think it's only fair to address the issue of miscarriage and miscarriages can arise from a variety of sources they can arise from genetic defects they can arise from issues in the milu of the uterus that can arise from issues with a sperm for that matter right we really don't want to put all the weight and all the um responsibility on the egg this is always an egg sperm Dynamic and when I say egg sperm Dynamic now hopefully that calls to mind the huge library of information that we've been covering up until now about uh chromosomal segregation and the coming together of these different cell types and their genetic information any number of different steps within the process of fertilization leading up to pregnancy can lead to miscarriage however the probability of miscarriage greatly increases as a function of the age of the egg and the basic numbers on this are that for women who are 35 years or older about 25% of successful fertilizations lead to miscarriages now when those miscarriages occur during pregnancy can be highly variable sometimes it's within the first trimester sometimes it could be later but the probability is about 25% that probability increases greatly over time such that by the time women are in their early 40s so 40 or older the probability of miscarriage after a successful fertilization is going to be about 50% and this could be due to a number of factors as I mentioned before but one common reason is that there can be chromosomal abnormalities and that could be related typically to the segregation of the egg when half of the chromosomes in that egg are removed taking it from diploid to haploid if you recall there's that little polar body which is the removal of the chromosomes that's ejected from the egg that will eventually ovulate and sometimes not all the chromosomes that were supposed to be ejected in that polar body are ejected and as a consequence there are multiple chromosomes or duplications of chromosomes things like tricomes sometimes too many chromosomes move away and they're actually removal of entire chromosomes meaning both strands so that you have chromosomal deletions and in that case typically fertilization won't occur but there are instances in which fertilization will will occur so a woman will get a positive pregnancy test her periods will stop and they the couple will think that they're advancing along uh the steps to a successful pregnancy and then there will be sadly a miscarriage many many times those miscarriages are the consequence of the fact that when there are extra chromosomes there or there are too few chromosomes present that embryogenesis can simply not progress in a healthy way um there are some instances in which all of the ch romes and all the chromosomal arrangements are perfectly normal and miscarriages can still occur I'm going to do a future episode about pregnancy and embryonic development where we will get into this more deeply but just understand that the frequency of miscarriages increases dramatically after about age 34 and then continues to increase traumatically uh extending well out until the 40s now a very important consideration in terms of understanding and predicting fertility and fundability this word that describes the probability of getting pregnant on a given try and over time is trying to address how quote unquote fertile a woman is and importantly how quote unquote fertile a male is and we'll talk about the male side in a moment but when trying to address how fertile a woman is of course age is going to be one of the major factors but just one factor right we already talked about how age determines the likelihood of a successful pregnancy if the Intercourse and ejaculation is being carried out at the correct times and with viable sperm capable of fertilizing eggs and then of course there's the issue of egg quality but in general most women would like to know how fertile they are as a function of their age right and I actually think this is one of the most important topics in this whole Space around fertility that isn't often discussed or at least isn't often discussed until women are in their late 30s or 40s when often times they will look back and wish that either they had Frozen their eggs or they had Frozen fertilized embryos which is a a whole thing um unto itself and we talk about that when we have an an episode on invitro fertilization in more depth but there is a fairly straightforward way or set of ways that women can determine their basic level of fertility leaving aside a lot of the detailed issues about the quality of eggs and so forth one thing that you already learned is that there's this Vault there's this Reserve that we call the ovarian reserve and that each month a certain number of follicles leave that reserve and there's the opportunity based on the ovulation of a single egg to fertilize that egg and for the woman to get pregnant now one thing that we know for sure is that the size of the population that's released from that Vault each month has a very strong positive correlation with the size of the reserve in the vault itself okay so the way to think about this perhaps is that the vault is like a bank account has a certain amount of money or in this case eggs in it and you could imagine if someone's reasonably logical that if they have more money in their bank account then they're going to withdraw a larger amount each month than if they have a small amount each month if the idea is to make that Vault that bank of eggs available to them over the longest period of time and indeed biology is pretty smart it doesn't deploy or release you know half the follicles in one month and then just slowly trickle out the remainder of follicles no that's not how it works what you find is that of course in younger women so say in their late teens 20s and 30s the ovarian reserve in the vault is going to have more eggs in it and the number of follicles and eggs that leave that Vault each month is going to be quite high so one way to evaluate how quote unquote fertile you are again just one way is to go to your OBGYN and say that you would like to know how many follicles you have in a given month and of course they'll look at them on both sides in both ovaries and for instance if a woman has you know just two or three follicles that are out each month well then the Assumption again it's just an assumption but the Assumption that's pretty good because there's this positive correlation that generally occurs is that that ovarian reserve that the number of eggs in the vault is fairly low compared to someone who say has 20 follicles or 30 follicles each month okay and that's the typical Trend again these are averages and it's very important to not get attached to any one number here again these are averages so for instance there are women who only deploy five follicles and eggs each month from out of their ovarian Vault but who find themselves to be very fertile and and there could be a number of different factors to explain that other women will have 20 or 30 eggs and follicles that leave that Vault the ovarian reserve each month and they will have a harder time getting pregnant for any number of different reasons but in general the more eggs and follicles that leave the Vault each month the higher number of eggs that are still in reserve meaning the greater amount of time over which a given woman could still attempt to have successful fertilizations now this um small collection of follicles and eggs that are released each month actually has a name they're called anro follicles these are small follicles they tend to be about 2 to 9 millimet across the way these are analyzed or measured is woman will go into the OBGYN office and by ultrasound typically is there's some local anesthesia but it's not often a general anesthesia but by local anesthesia sometimes no anesthesia they will essentially count the number of follicles that are present in each side on ovary on the left and the ovary on the right and give a woman some sense of how many follicles she has and typically this is done over a series of months to determine how many eggs are leaving the ovarian reserve each month and therefore how many eggs she is likely to still have in the ovarian reserve Reserve now there's a non-invasive way to do this as well although typically an OBGYN will do both what I just described with ultrasound and measure something called amh which is antimullerian hormone which is a hormone that is released by that anof follicle population the population of follicles and eggs that leave the ovarian reserve each month so one is a blood draw measure of a hormone amh the other is a structural Imaging measure of the Antro follicles directly again the typical trend is for the number of anro follicles to decline over time so one might expect for instance that a woman in her 20s or 30s might have 20 30 maybe even 40 anro follicles that are exiting the reserve each month and again that's the total across both ovaries again these are just averages these are going to be distributions there will be people with far fewer there will be people with far more but that overtime regardless of where a woman starts out from one decade to the next half decade and decade and so on that the number of anal follicles will Decline and the amount of or the levels of amh will also decline so what does this all mean what this means is that if you are a woman who is in her 20s or 30s or 40s whatever your age if you are interested in conceiving in the future it's very likely a good idea to go to your OBGYN and get either your amh levels measured or your follicle count measured and to do that several times in a given period and I don't mean a menstrual period I mean a given period of time across several months to determine what is the average number of follicles what's your average amh level thereby giving you some window into how many eggs you are likely to still have in your ovarian reserve I cannot tell you how many women that I've spoken to and how many OBGYNs more importantly because they speak to many more women about this than I ever have or ever will wish that they had done this earlier right they think oh well I'm I'm in my 20s so I'm likely to have a ton of follicles or they got pregnant once before and so they're not so concerned about the number of follicles or their amh levels but over and over again I was told in researching for this episode that the earlier and more frequent that women do this procedure of measuring amh and measuring their follicle count the higher the probability that they will eventually have a successful Fertilization in pregnancy when they seek to do so now the mirror image of all this of course is the sperm and you know there's a kind of common misconception out there that you know the sperm you only need one and indeed you only need one but actually you need many and it's only one that's able to successfully fertilize the egg so this whole concept of you only need one is um both dismissive of the sperm but more importantly dismissive of the biology of the sperm and the Egg okay it only takes one successful sperm and one successful egg but that's sort of like telling a woman hey you only need one egg right you need one egg of sufficient quality in the right time time and place and you need one sperm of sufficient quality in the right time and place in order to get successful fertilization and hopefully pregnancy but you need a lot of sperm in order to get a high probability that that one sperm will be able to successfully fertilize the egg so we have this image of sperm as kind of these um dumb operators that just sort of swim uh mindlessly towards anything and if they bump into an egg then they fertilize the egg and that's really not the way it works as I talked about earlier the sperm with its head its mid region its tail choco block with mitochondria in the mid region is really an active motile cell that indeed will just swim forward if it's a healthy forward progressing sperm but you many males out there just simply do not have any knowledge of how many quality sperm that they happen to have now given the fact that sperm analysis is relatively inexpensive and also the fact that freezing sperm is relatively inexpensive I think it stands to reason that most men should at least get some window into the numbering quality of their sperm now it's a fair assumption to say that if someone is in there late teens or early 20s or 30s that they probably have high quality sperm but again as with the egg and the importance of measuring amh and follicle count across time men should really evaluate the quality and number of their sperm and we talked a little bit earlier about some of the parameters that uh urologists and OBGYNs like to see when evaluating sperm right you know there's a minimum number or concentration of sperm that they like to see if a couple is going to use IVF in vro fertilization and typically that's going to be about 15 to 20 million per Mill of of sperm or semen and typically they want to see somewhere between two and five milliliters of semen um overall in a given ejaculate after a 72 to 48h hour abstinence period because of course the more ejaculations the smaller the the volume of the ejaculate um in a short period of time but after 48 to 72 hours you more or less maximize the volume of ejaculate and then of course they want to see 50 but typically 60% or more of motile sperm in order to get IVF but it more is better and of course there is an enormous range as I mentioned before some males will have anywhere from 10 to 20 million sperm per milliliter of ejaculate and some men will have 100 to 200 million okay but just because they have 100 to 200 million doesn't mean that all of those sperm are of high quality and can fertilize eggs sometimes the more than half will be twitchers and some will be immotile and so on and so forth so it's very straightforward what I believe most people should do and what the urologists I spoke to in advance of this episode said to do which is to Simply do a sperm analysis refrain from ejaculation for 48 to 72 hours give a sperm sample have that sperm sample analyzed the cost of the sperm analysis is not typically that much okay and considering that conception and healthy conception and fertilization is an expensive process if you have to go the invitro fertilization route it stands to reason that the cost is pretty well Justified you also have the option to freeze sperm over time there is evidence that the age of the father and therefore the age of the sperm can dictate whether or not there's a higher instance of problematic pregnancy or developmental outcomes including autism that is true you probably heard that if the father is 40 years or older the incidence of autism is increased significantly that is true although the overall probability of having an autistic Offspring if somebody if the father that is is 40 years or older is still quite a bit lower than you would imagine it's not as if the probability suddenly skyrockets okay so that we'll have an episode on autism and genetic and non- gentic um influences on autism and other aspects of the autism spectrum but the point is this I believe and the urologists I spoke to who are interested in fertility and male health and Sexual Health suggest that men get their sperm analized at least once every 5 years and certainly if they're going to want to conceive children in the distant future that they consider freezing their sperm because that too is fairly nominal cost in order to freeze sperm at a younger age and of course if you can freeze and use sperm from the time in which you were younger why wouldn't you right I mean you can still opt to go for natural pregnancy later later if that's what you want to do but having that in reserve is um generally a good idea and I discuss some of the parameters that are that are looked for and perhaps most importantly there is the possibility of an underlying issue whereby for instance there is very little sperm in an ejaculate as I mentioned earlier the seminol fluid in the ejaculate could have zero sperm in it but the volume of ejaculate could appear completely normal so just because your ejaculate volume is uh normal to you or is in that range of you know 2 to 5 milliliters well then that doesn't necessarily mean that there are any sperm there or that there are very few sperm there and the few sperm that are there or the many sperm that are there are functionally motile so get this analyzed it's really worth doing and again it's not something you have to do every year it's something that you want to do probably every five years at least until the point where you've conceived as many children as you ever want to conceive so the basic takeaway here is that if you're a woman to get your egg count your anal follicle count that is and therefore your reserve of eggs indirectly measured and of course also get your amh levels measured and if you're a male to have a sperm analysis and to do that relatively early in fact another incentive for doing that early is that you have a comparison point so that for instance if you are in your early 20s and you're not thinking about having kids at all or you're thinking that you might someday have kids but it's a really someday someday far off in the future well it's wonderful to have a reference point from which to compare your biology in your early 20s to your biology in your mid or late 30s or 40s when you might happen to be interested in conceiving and if that doesn't provide incentive enough I should mention and this is important to point out and that I think both males and females are not aware of is that one in five couples that have issues with fertility the issue ends up falling on the biology that is the quality of the sperm or a lack of number of sperm so you know I think there's a misconception that when fertility is in it's always an issue with the eggs um and this age dependent uh decline in egg quality again it's the best language we have available to us at the moment this age dependent decline in egg quality is often to blame but not always one in five couples that have challenges conceiving turns out that it's going to be an issue with the sperm and of course there are a number of different sperm analyses that should all the other parameters of sperm appear normal now for instance you can get a DNA fragmentation analysis you can see whether or not the DNA of the sperm are somehow disrupted urologists these days are excellent at figuring out for instance if a male has lots and lots of sperm everything looks great but the shape of the head of the sperm isn't quite right if it's not oval enough and it's too rounded that could be a genetic defect under which conditions there is zero probability of the male ever naturally conceiving right regardless of who the female partner is Believe It or Not males can have a ton of sperm but if they carry a certain genetic defect those sperm will be incapable of depositing those 23 chromosomes into the egg however there are ways in which that sperm can be coaxed or forced to fertilize the egg and deposit its genetic contents by invital fertilization and then implantation into the female so again lots of reasons to have a egg Reserve analysis by ultrasound and amh for females and lots of reasons for males to have a sperm analysis and of course typically with a sperm analysis and a ovarian reserve analysis will be a hormone analysis and I'm a very strong believer in people getting an Insight that is a window into their hormonal composition not just when they encounter problems but starting at a pretty early age even if it's only done once every five years or so having a reference point to your 20s and to your 30s and mid-30s for when you felt a certain way maybe as in the case for many people I know they actually feel better in their 40s than they did in their 20s because they're doing a lot of things to support their health that is possible but in many cases people start feeling not as well or their fertility seems to be dropping off or any number of different parameters that we've discussed today were related to vitality and Longevity seem to be dropping off over time and they want to get a insight into what could be the issue and hormones are sometimes not always but sometimes involved in those underlying issues and there's nothing as valuable as having a reference point from a time in which things were going well to evaluate the for instance the levels of hormones not just testosterone but also estrogen and progesterone and so forth so you need a comparison point in order to determine what really needs to be changed so all of this is a um strong push for people to use your insurance if you're able to put it on insurance oftentimes um people are and if not to try and find a reasonable or reasonably U priced way to do a sperm and egg analysis and to ideally do a hormone analysis as well it's really going to set you up for the maximum probability of being able to conceive children when you want to and also So to avoid a bunch of other health related issues that involve hormones and reproductive health and in general to support your mental health and physical health so I've been talking about a bunch of things to do there are a couple of things to be mindful of to actively avoid if your goal is to be and remain fertile and that's regardless of whether or not you want to conceive children in the future or not now in the context of this discussion the same things that we've heard to be true for other aspects of our health turn out to also be true so so let's just start with the basics everybody should be getting approximately 6 to 8 hours of sleep every night that should be quality sleep optimizing your sleep is fundamental to balancing your hormones now balancing your hormones is kind of a catchphrase for all things related to proper hormone regulation sleep is the fundamental layer of mental health physical health and performance of all kinds and believe it or not fertility when people are not sleeping well or enough stress hormones in particular cortisol shift to to peing later in the day and those elevated cortisol levels later in the day cause a bunch of different problems in both males and females many of which impact fertility so controlling cortisol starts with controlling your sleep it also impacts testosterone and estrogen levels so of course the proper ratios of testosterone and estrogen will vary from males to females but in order to get those right or as right as they can be without other interventions you want to make sure you're getting enough quality sleep how much sleep most people need about 6 to 8 hours of sleep per night waking up once maybe twice per night in the middle of the night and going back to sleep is not such a big deal but 68 hours of solid sleep would be ideal some people need a little bit less in order to function you know 5 hours some people need a little bit more developing teenagers and babies and kids need a lot more people who are sick or recovering from injury need a lot more we've done multiple episodes on sleep we have a toolkit for Sleep available free at hubman lab.com you go there you don't even have to sign up for the newsletter although you can if you want just go to toolkit for sleep under the menu and you'll be able to download that or you can even just view it on the screen if you don't want to download it has lots of tools we've done an episode called perfect your sleep that has a lot of tools they're all timestamped for you you've done a master your sleep episode so lots of tools to get your sleep right get your sleep right if you are wishing to conceive Andor to Simply have healthy biology to be fertile or otherwise that's just fundamental now there are other things to not do and those again fall into the somewhat obvious categories but I think a lot of people aren't aware of just how striking an effect these certain behaviors that you want to avoid can have in diminishing your fertility for both males and femal so let's talk about those so the first one is smoking and when we talk about smoking here we're talking about smoking nicotine and we're talking about smoking cannabis and indeed there are strong data and I will put a reference to one of the better larger analyses of these data there are strong data showing that cannabis reduces fertility now I can already hear the screams from the back although they're probably um fairly drawed out screams from the back of people saying they smoked cannabis and they had no trouble conceiving certainly there will be exceptions but whether not you're male or female smoking cannabis is a bad idea if you want to conceive a healthy child can you still conceive a healthy child while smoking cannabis probably certain people can many people will greatly decrease the probability of a healthy fertilization and pregnancy by smoking cannabis there are excellent data to support that as well nicotine both smoked or Vaped is going to disrupt the process of fertilization and can disrupt pregnancy dramatically okay so just avoid it all together how does this happen well it turns out that smoking increases what are called reactive oxygen species this greatly disrupts the quality of the egg at the level of the spindle and mitochondria and a number of other features and in the sperm turns out that smoking doesn't necessarily disrupt the sperm directly although it can cause DNA fragmentation with which can cause all sorts of abnormalities can prevent fertilization can lead to birth defects in The Offspring but more importantly it increases what are called reactive oxygen species in the seol fluid in the semen that contain the sperm this very under normal circumstances under healthy circumstances beautifully orchestrated chemistry of fluid that allows a sperm to thrive in their trajectory and attempt to fertilize the egg and lead to a healthy pregnancy so if you are a smoker and you want to conceive the best advice I can give you is to quit smoking and yes that includes cannabis as well now I am not somebody who believes that cannabis across the board is not useful there are medical applications and other applications I talk about that in an episode all about cannabis for health and disease and notice Health was in there too so you cannabis smokers don't come after me with I guess whatever it is with um bongs and pipes or whatever it is that you want or with Vapes the point is that while it can be beneficial for certain populations it's certainly bad for others and if you're trying to conceive it is bad for fertility and for a healthy pregnancy okay now that's smoking uh and vaping by the way okay vaping is included there now the next category of don'ts relates to alcohol now everyone has heard that drinking during pregnancy is a bad idea you may have heard and some people have talked about the fact that there are cultures in which they allow if you will or even condone sadly one or two drinks while pregnant provided it's just champagne or something of that sort that is a terrible idea I did an episode all about alcohol both its potential health effects of which there turn out to be zero and yes that includes red wine it is far better to not drink at all and if you're going to drink the limit if you're a healthy adult who's not trying to conceive not pregnant and you don't have issues with alcoholism is probably two drinks per week total that's right two drinks per week total and that's the level that you really should consider if you're a drinker if you're somebody who's trying to conceive however for woman who becomes pregnant the tottal number of drinks that you should allow yourself per week while pregnant and breastfeeding is indeed zero there is absolutely no evidence that one can quote unquote get away with drinking during pregnancy and people say well I had a perfectly healthy child but of course you don't know what the health of that child would have been had you not drank at all now I'm not here with any generally strong stance against alcohol I myself am somebody who has a drink every once in a while although I'm don't consider myself somebody who has a strong proclivity for alcohol and of course I'm at this moment I'm not trying to conceive children and I'm certainly not pregnant so that's safe for me um but frankly I haven't had a drink in a very long time and so I don't miss it and that's me but I do realize that a lot of people enjoy alcohol and so it's that two drinks per week limit that really sets the upper limit and threshold Beyond which you start running into issues with cellular mutation you start running into issues of oxidative stress greatly increased cancer risk in particular breast cancer risk all that's covered in the alcohol episode that we did you can find it hubman lab.com and timestamped if you want to navigate to specific topics and so forth find out all about the data supporting the statements that I'm making so on and so forth now if you're somebody who's seeking to conceive or you fall into this category that some couples describe themselves as we're not trying but we're not not trying meaning they're not using birth control they're kind of letting chance run its course well then you should definitely be aware of the data showing that even just one bout one bout of so-called binge drinking which is five to six drinks in a given night or half day in a 12-h hour period one bout of five to six drinks if you're a woman or you're a man greatly increases both the likelihood of mutations in the embryo that would result from a fertilization and at the same time for reasons that should be obvious to you based on all the biology we've talked about a greatly reduced prob ability of fertilization now that absolutely does not mean that you should use the ingestion of five or six drinks as a method of birth control that is not what I'm saying here what I'm saying is is that if you go out on a given night and you have five or six drinks and you happen to become pregnant the probability that that pregnancy will be disrupted in some way is greatly increased what the exact consequences are no one can tell you but also if you're somebody who is interested in conceiving a child well then you absolutely should abstain from ingesting drinks more than one or two during the time in which you're trying to conceive and ideally it would be zero and you certainly would want to avoid drinking multiple drinks per night and so this idea of going out and having you know three or four drinks or four or five drinks in a given night at a time in which you're also trying to conceive children the biology tells us the epidemiology tells us that this is just a terrible idea it's going to reduce the lik Ood of fertility and successful pregnancy and if there is a successful pregnancy the word success needs to be in quotes right I mean I think every parent every species for that matter wants to increase the probability of having healthy Offspring and so uh to my mind anyway and to the OBGYNs and the urologists that are focused on fertility that I spoke to everyone will say try as hard as you can to avoid these so-called binge drinking episodes and again these episodes are one night of consuming five to six drinks now another important thing to remember in this context is that the negative effects of consuming five or six drinks in a given night extend over many weeks following the ingestion of that alcohol if you're a male what that means is that's going to impact the quality of your sperm and greatly decrease the likelihood of successful fertilization Andor healthy pregnancy over the period of that entire spermatogenesis window which is as we talked about before 60 to 90 days right 60 to generate the sperm and then in some additional time for the sperm to be transported to the point where they could be ejaculated if you're a woman and you have five or six drinks on a given night well then you are going to disrupt the quality not of just the egg that eventually ovulates but indeed the entire pool of follicles that leaves the ovarian vault in reserve and from which the one egg will be selected in other words you are reducing the quality of all of the eggs that you happen to deploy that month now some of you who were really following the biology earlier might say what if I have those five or six drinks during the time in which I'm menstrating just in which there's bleeding present and therefore I haven't yet ovulated ah but if you remember the biology we talked about earlier specifically there is a subset of follicles and eggs that leave that ovarian reserve quite a bit before that one egg is selected for and ovulates and of course there are all the different hormonal Cascades and the general Mill U of the ovary which are important and are being regulated by different hormones and yes indeed the regulation of those hormones is strongly impacted by alcohol through a number of different pathways through the regulation of the neurotransmitter Gaba up in the brain right it's actually a lot of Gaba and Gaba receptors in the hypothalmus the very region from which gonadotropin releasing hormone our old friend from a couple hours ago in this discussion going to disrupt G&R secretion you can disrupt pituitary function with alcohol again and again what we're seeing is that consuming more than one or two drinks per week of alcohol is really detrimental to the entire process of fertility and the entire process of healthy pregnancy and that's true from both the male side and the sperm and it's true from the female side and the Egg so my simple advice on this is if you are wishing to have a healthy fertilization and pregnancy the best thing to do would be avoid alcohol together and if you're going to drink to really limit that drinking to one or two drinks per week maximum so those are the major or don't really avoid excessive stress and I should mention excessive stress is not just best avoided by getting enough quality sleep at night although that is the primary way there are other ways to avoid stress we've done entire episodes about this and we have a toolkit related to reducing stress with very simple zero cost tools again you can find all that huberman lab.com I should mention if you want to find any episode or topic or timestamp that website is keyword search available so you can just go to hman lab.com put into the search function stress tools and a bunch of different links pop up related to those topics um likewise with sleep likewise with any number of different topics you might be interested in so get enough quality sleep and thereby reduce stress and also directly buffer stress with real-time tools to buffer stress that I've talked about um in the episodes that you can access and there are ways to greatly reduce your overall level of stress to limit any cortisol that's released to early in the day which is when you want cortisol released and not have it late in the day and so on and so forth so reduce your stress and as I just told you by all means do not drink more than two drinks per week and zero is better than two if anyone tells you oh well there's you know all this uh Resveratrol in red wine and that's good for us the data simply tell us that there's not enough Resveratrol in red wine to really have any positive health benefit the data around res trol and health benefits itself is under question nowadays zero alcohol is better than any alcohol two drinks per week is the limit also limit or eliminate or avoid nicotine and ideally cannabis smoking and vaping at the time in which you trying to get pregnant and certainly if you are pregnant avoid all of the things as best you can that I just described a moment ago now there are a couple other don'ts that are really important um one of the most important don'ts relates to STI or sexually transmitted infections everyone who's sexually active should get an STI check in fact if you go to a fertility clinic or you go for sperm analysis or you go for egg analysis almost always they will do an STI check even if you happen to be in a monogamous relationship even if you happen to be not sexually active and you're somebody who's seeking to use IVF with a sperm donor or something of that sort why would they do that why why is there so much concern about that is it about avoiding um giving birth to a child that um has um something like a herpes infection or something or HIV well certainly that's one reason but that's a down thee line reason because at the time when someone goes into the clinic for one of these sperm or egg analyses I mean that's well in advance of any pregnancy right the reason is there are are a number of STI in particular chlamydia for which it greatly increases the probability of miscarriage so chlamydia is one of those um very Insidious and cryptic STI because a lot of people both males and females don't even realize that they have chyia and then they can carry Cham at the time in which they conceive and then that can lead to ectopic pregnancies and or miscarriages so by all means get an stti check if you are somebody who's seeking to conceive children or evaluating your fertility generally CIA can also have damaging effects on the epidemis and on the various other aspects of male reproductive Health in the future we will do an episode all about sexual health this is not the time for that but get an STI check if your goal is to conceive a healthy child now the other thing that can have a very negative impact on fertility and healthy pregnancy is a viral infection uh for instance if a male has had a severe viral illness and this could be any number of different viral illnesses from flu to cold or any number of different viruses pick your favorite virus in the previous 70 to 90 days that can greatly diminish the number Andor quality of sperm okay so that's really important this is also important if you're going to go in and do a sperm analysis and you had a viral infection in the previous 70 to 90 days well then you need to be aware of that because it could greatly impact the parameters of that sperm analysis likewise for women if you've had a serious viral infection in the previous 30 days does that mean you should not try and conceive not necessarily but you should talk to your OBGYN about that there are data showing that viral infection in particular of influenza in the mother in the first trimester of pregnancy has some correlation it's not 100% but some correlation with negative mental health outcomes of The Offspring sometime later including schizophrenia this is some of the work that was done at Caltech a number of years ago um and other Laboratories as well those data are still being built up over time again it's not one for one it's not causal so uh if you did get an influenza or cold or other kind of viral infection during the first trimester or any trimester of pregnancy um I don't want to cause alarm but you should talk to your OBGYN about this the goal of course is to avoid viral illness at any time when you're trying to conceive or have healthy pregnancy but of course um sometimes people will get ill and the children can turn out to be perfectly normal and fine but it is something that you want to avoid and it will impact your egg analysis and it will impact sperm analysis now one thing I found really surprising in researching this episode was that one in 25 men carry a copy of a mutation for Cystic Fibrosis now some of you are probably familiar with cystic fibrosis as a condition that can cause um issues with the lungs the accumulation of fluid in the lungs or other tissues cystic fibrosis in order to express that way of accumulation of fluid in the lungs you really need two copies right you need two Mutant copies or you need two copies of the cystic fibrosis Gene one in 25 men will carry Just One Cop and therefore will not have any symptoms of cystic fibrosis but those one in 25 men will have defects in the architecture of the vast defin the duct through which the ejaculate needs to pass in order to eventually be ejaculated out of the urethra and so what that means is that these men can have what appears to be normal semen volume but that they won't have normal numbers of sperm and that's not because of a deficit in making the sperm the test can function just fine the brain and the pituitary communicating with the testes just fine but that literally the passageway by which the sperm arrive within the seminol fluid and it eventually ejaculate is disrupted by the cystic fibrosis Gene luckily if somebody has just one copy of the cystic fibrosis Gene and they're male and this is the issue the vast Defence either can be repaired by a urologist who's expert in the surgical repair of vast deference or sperm can be extracted from the testicle directly which might sound like a painful procedure but I believe nowadays um in talking with various experts on this turns out that it can be done with a minimum of discomfort and certainly if the goal is to have a healthy child you're going to need those sperm so you're going to want to get them uh one way or the other regardless of the discomfort now before getting into some of the things that you can do in the positive sense to increase your fertility we do need to touch on just a few other things that you want to avoid in order to avoid diminishing your fertility and this mainly relates to males but it will also be relevant to females and of course of course when I say also relevant to females I'm referring to the fact that if it's a woman and a man who are trying to conceive um then she of course is going to be interested in her egg quality but also the sperm quality and of course there are women who are conceiving by way of sperm donor through IVF or IUI or otherwise but in any case the need to understand and maximize the quality of both the egg and the sperm is Paramount so in order for men to maximize the quality of their sperm as I mentioned earlier does not seem to be big difference whether or not they use boxers or briefs or whether or not they quote unquote go commando they don't wear any boxers or briefs of any kind however it is important to keep the testicles cool enough they need to be about 2 degrees cooler than the rest of the body and there are a number of different ways to do that as I mentioned before avoid going in hot tubs During the period in which you're trying to conceive children you should also avoid going in saunas During the period in which you are trying to conceive children and if you do go in the sauna you can bring an ice pack there and you can put it on the testicles in order to offset the heat of the sauna and keep the testicles cool while in the sauna the other thing that you'll definitely want to do is avoid putting a laptop or any other hot device directly onto your lap there are a number of different um devices that you can put on your lap you could put books or a box or there are these devices that are designed to um dispel the heat from the laptop I would say if you're trying to conceive just keep the laptop off of your lap just put it on a table or standing desk or whatever just keep it off of your lap also there are some really interesting data showing that the amount of time that men spent sitting regardless of whether or not they sit with their ankle on their opposite knee or with knees spread you know the classic manspread stance or um or any other kind of seated stance is going to increase the temperature of the scrotum for reasons that are somewhat obvious if you think about the architecture of all this I think both men and women if you put enough thought to it you oh yeah that would increase the temperature obviously avoid um seat heaters in cars or otherwise but reducing the total amount of time that you spend seated is really important if you want to keep the temperature millu of the scrotum optimal for sperm quality and fertilization and as I mentioned earlier it's going to be important to make sure that your legs are not really big to the point where they are creating a hotter than is healthy environment for the scrotum and testicles so a hotter than normal EnV for the testicles can be caused by legs that are very large upper thighs that are very large due to obesity or due to those upper thighs being too muscular so by all means don't skip leg day but be aware that if you're somebody who's trying to conceive you want to do whatever you can to reduce the temperature of the scrotum or at least not let it get too hot for too long okay so um I can think of all sorts of um uh reasons now that men are going to come up with to um do the manspread stance of their knees really far apart even further if they have large legs that's not a discussion we want to have here and that's not really what today's discussion is about really the principle is what's most important which is to keep the temperature of the scrotum and testicles lower than the rest of your body there's a direct blood flow from the body to the testicle that provides blood flow it's designed in a way that that blood pathway should be outside the body and as far away from the body as possible in order to get the temperature millu of the scrotum in testicle correct for healthy sperm quality now a topic that is sure to be a bit controversial but it really shouldn't be because the data at least to me are very clear is this issue of phone use and sperm quality now this can open up a whole array of issues related to things like emfs and you've got people out there that have you know ideas about 5G and all of this stuff that is not what this discussion is about the discussion I'm about to have with you relates to the fact that the electromagnetic fields and the heat related effects of smartphones can indeed have a detrimental effect on sperm quality and yes indeed on testosterone levels as well I'm going to refer you to a paper uh we will link it in the show note captions the title of this paper is effects of mobile phone usage on sperm quality no time- dependent relationship on usage a systematic review and updated meta analysis this is a paper that came out in 2021 and talks about the fact that phones emit a radio frequency electromagnetic waves which are called called RF radio frequency emws electromagnetic waves at a low level between 80 and two 2200 MHz that can be absorbed by the human body we know this okay this is not controversial and have potential adverse effects on brain heart endocrine system and reproductive function that has been established keep in mind there is basically no controversy that radio frequency waves and emfs can have a negative impact on biological tissues the question is how intense are those radio frequency waves and emfs and how detrimental are those on those biological tissues okay it's a matter of degrees but there is very little controversy as to whether or not they have an effect on biological tissues and I'm aware of absolutely zero data showing that they can have a positive effect on biological tissues since what we're mainly talking about now are smartphones we want to separate out the heat effects of smartphones from the emfs related to the fact that they are Wi-Fi smartphones or they're using Cellar towers and Wi-Fi one or the other a combination okay so they're number of different things in the phone that could be detrimental we need to separate those out why well because you might have heard that carrying your phone in your pocket can reduce your testosterone levels and sperm count and guess what that is true the data contained within this metaanalyses and other meta analyses clearly point out that it can reduce sperm count and maybe testosterone levels significantly but certainly sperm count and motility significantly it reduces sperm quality so should you avoid putting your phone in your pocket your certainly your front pocket I would suggest yes right if you are somebody who is seeking to conceive right I'm not somebody who is going to stop using my smartphone I don't expect anyone's going to stop using their smartphone the question is should you carry it in your front pocket if you're a male I think to be on the safe side the answer is probably avoid doing that too much of the time ideally don't do it at all then people will say well what if I turn off the Wi-Fi or I turn off the cellular access then is it still a problem well it's a problem due to the heat related effects and then people say well I don't actually feel the heat of the phone it doesn't get that warm but the temperature effects of the phone it turns out are enough even under conditions in which people don't report it to be uncomfortably warm that it can change the temperature milu of the testicle in ways that can diminish sperm quality how much and how that relates to fertility and healthy pregnancy not clear but since we're talking about things to avoid if your goal is to have a healthy fertilization pregnancy well then by all means just don't carry it in your front pocket then people say well what about back pocket or what about backpack look it's very clear that avoiding being too close to the phone is probably better for your sperm quality than putting the phone very close to your testicles or anywhere else on your body but it's also the reality that most people are going to carry a phone nowadays all right it's just the reality I think I think the current um estimates as discussed in this paper that 90% of the human population has a smartphone 90% which is incredible the adult population of course although a lot of kids have them as well so this paper goes on to detail a number of different studies and outcomes from studies but basically what they find and here I'm paraphrasing is that uh the data indicate that sperm quality declines when people start using a mobile phone so from the point they start using a mobile phone regardless of the usage time this is important it used to be thought that it was 4 hours a day or more of holding your phone or having that phone close to your body was going to diminish sperm quality it turns out that it's not related a usage CH that's even the Tittle of the paper it's just the fact that people are using mobile phones is reducing sperm count and quality that's the reality is it entirely responsible for all the reductions in sperm quality and maybe even the reductions in testosterone levels that we're observing from decade to decade going forward I doubt that's the case is it likely to be one of the major players I've got my bet on the fact that it is based on the data that I've observed and so if any of you would like to peruse the data in this met meta analysis they're quite good this looked at 18 studies that include 4280 samples they were able to separate out the radio frequency versus the Heat effects and they were able to eliminate this time of usage um variable that previously we thought if you were exposed to a lot of um cell phone contact that it was far worse than if you were exposed to a little bit turns out if you're exposed to any at all you're going to diminish sperm quality what does that mean does that mean that no matter what you do if you own a smartphone that you're going to diminish sperm quality I think the short answer is yes but that you can mitigate it what might you do well keeping your phone away from your groin or as far from your groin as possible if you're a male who's wishing to conceive and maybe even a male who's wishing to maximize his testosterone levels because it does appear that radio frequency waves and the heat from the phone so both of those factors independently and together of course can disrupt the liic cells of the testes and the production of testosterone and in testicular testosterone is important for sperm production the exact biological variables leading to all these changes isn't exactly CLE but if you're like me you say okay probably not a problem for most males to carry their phone but probably best to not carry it in the front pocket maybe even avoid carrying the back pocket as well again in the future we will have an episode all about Bluetooth we'll talk about um various aspects of emfs it's a super interesting uh data set and it's a data set which there's a ton of controversy um it's uh really interesting however and there more and more quality data coming out all the time and I think going forward we are going to see that indeed there are some negative effects of smartphones related to both their radio frequency um transmission and the fact that they generate heat and in general heat is not good for biological tissues so any discussion about heat and sperm and how heat is detrimental to sperm has to raise this issue of whether or not cold is good for the testicle okay well now there's a lot of data starting to come out about the positive effects the positive biological effects of deliberate cold exposure on different aspects of brain biology such as the release of dopamine and norepinephrine and on the biology of the body to some extent metabolism but more so the impact on Brown fat stores which are good for us so-called Brown fat thermogenesis there's a lot related to deliberate cold exposure and we've done entire episodes on deliberate cold exposure again you can find that at hubman lab.com we did a guest episode with an expert on the use of cold for health and performance with my colleague Craig heler from Stanford Department of biology we also have a toolkit on how to apply deliberate cold exposure for health for both females and for males for sports performance cognitive performance mood sleep Etc you can find all that again hubman lab.com totally zero cost just go into the menu go to newsletter and scroll down and you'll find those when thinking about sperm quality we want to remember that excessive heat is bad now does that mean that deliberate cold is good well it turns out that one of the major causes of lowered sperm count and overall reduced sperm quality that's quite common is the presence of what's called a vericel a vericel is kind of like varicose veins of the veins that innervate the testicle and what it essentially does is it means that blood will pull in the testicular region it can't circulate back to the body quickly enough and therefore the temperature of that environment increases there's some other things that ver cells do which can be obstructive at the physical level so they're not just temperature related it's pretty clear that using deliberate cold exposure can be healthy for the sperm because of the ways not that cold directly supports testosterone or sperm quality but rather because cold reduces heat okay so you will find um available online um I think they're actually called um forgive me but that's what they're called I didn't name them called snowballs these are um uh they're sort of like gelack uh cold briefs that uh you can buy and and men will wear for some period of time I I don't think you wear them all day you wear them for some period of time a lot of people are now using cold showers and Ice baths and circulating cold baths or going into a cold ocean or lake for any number of different reasons I talked about earlier I myself start every day with either a one to three minute cold shower or one to 3 minute um immersion up to my neck in a cold bath you know cold um water circulating water or a cold shower I do that mainly for the psychological effects related to the long-lasting increases in dopamine and epinephrine but there are other data starting to come out showing that that that sort of approach or similar approaches can increase testosterone levels and maybe even sperm counts can reduce cortisol late in the evening if the cold exposure is done early in the day so on and so forth so a lot of interesting data coming out in really good journals that are peer-reviewed and so on in humans I should mention those studies are done in humans to support the use of deliberate cold exposure but again if you're going to use deliberate cold exposure to improve sperm quality can it work yes indeed it can work either indirectly by increasing testosterone or directly by improving sperm quality but both of those effects are likely to be indirect by virtue of reducing the temperature of the testicle overall not because there's any sort of magic effect of cold on the testicle now I have to imagine that a number of you in particular the females listening to this are going to say is deliberate cold exposure and for that matter is deliberate heat exposure like saor or hot tub good or bad for the ovary for eggs and for fertility now there there fewer data to look to unfortunately but what we do know is that deliberate cold exposure done in the way that I just described 1 to 3 minutes a day ideally early in the day through cold shower or immersion up to the neck doesn't have to be an ice bath could be cold circulating uh water or even non-circulating cold water and people will say well how cold I should have mentioned that before how cold there is no way I can tell you exactly how cold the water should be because for some people 60° Fahrenheit will be exceedingly cold for other people 40° is going to be more appropriate how cold should you make it if you're going to embrace these practices you want to according to the literature what you want to do is make it uncomfortably cold such that you really want to get out but safe right you don't want to go into 30 Dee water um immediately you can actually have a heart attack and die if you do that so you want to progress gradually into the cold so you don't want to shock your system too much although it is the adrenaline evoked by that that quickening or shortening or elimination of the breath for a short period of time when you get into uncomfortably cold water that correlates with or is actually the reflection of would be more accurate to say the release of adrenaline and then dopamine and so forth which has been very well documented so uncomfortably cold but safe to stay in and I cannot tell you an exact number that is uncomfortably cold but safe for you it's going to differ person by person you want to figure that out just like I can't tell you how much weight that you should squat in order to achieve some effective uh resistance training for the legs it's going to differ depending on um your strength and your prior experience and so forth so ease into it be safe but it does appear that both for men for reasons I talked about a few minutes ago and for women that deliberate cold exposure can be beneficial for fertility and for hormone production but in particular for females in terms of regulating cortisol and for hormone production now you might say okay getting into cold is stressful how can that be helpful for regulating stress well it turns out when you get into the cold you get a big surge in Adrenaline and then dopamine which is very long lasting provided that's done in the early part of the day so I say you know not too close to sleep then what you do is you restrict your maximum cortisol release to a period earlier in the day that buffers reduces that is the likelihood that you would have excessive amounts of cortisol later in the day which not only can disrupt sleep but is correlated with a number of other um hormonal effects that are not good for us and therefore not good for fertility so here what I'm describing are positive yet indirect effects of the cold on hormone levels both in males and in females so for men we talked about increased testosterone improved sperm quality that was indirect right you're reducing the temperature of the testical but it's not that cold itself is positively impacting those things does that make sense heat is bad therefore reducing temperature is good likewise with females deliberate cold exposure can be good for the overall fertility process not because cold is good for the ovary or being cold is good for the ovary or for luteinizing hormone or for follicle stimulating hormone or anything else like that but rather that using deliberate cold exposure as a way to restrict stress in a deliberate way to a particular time of day increases the release of cortisol then and indirectly reduces the amount of cortisol that's released at other times along the 24-hour cycle okay so these are positive yet indirect effects so if you're a woman who really um is interested in exploring deliberate cold exposure or who enjoys it or is already doing it and you're wishing to conceive great explore it do it safely of course but explore it in to do it however if you're somebody who just hates the cold and doesn't want to go anywhere near it there's no reason to think that you absolutely need it provided that your stress your sleep and other factors are all being carried out properly the next things that we'll talk about in terms of positive things or things that we can do in order to maximize fertility for both females and males are the things that you also generally hear about elsewhere right along with sleep and avoiding alcohol and avoiding nicotine and avoiding cannabis avoiding excessive heat for the testicle avoiding excessive stress is that you want to try to get enough exercise right why would exercise have anything to do with any of this well exercise and that is both a combination of resistance training and cardiovascular exercise is going to improve the health of the mitochondria in particular cardiovascular exercise and I realize that for you Fitness Experts out there anytime someone says cardio people kind of roll their eyes like what is that you know there's endurance training there's interval training there's hit training there's Sprints there's all sorts of different things some of those overlap some of them are separate indeed that's the case but we can use a general rule of thumb here which is that for most people getting anywhere from 30 and ideally 45 to 60 minutes of exercise per day for six days per week maybe even seven but most people like to take a day off or need to take a complete day off each week six to seven days per week is going to be good for mitochondrial health and function it's also going to impact all the other things like quality sleep mood reducing stress and so on and so forth so exercise we can handle pretty quickly um by just saying everyone should be doing it um now when people are pregnant they might have to of course change the amount of exercise or the type of exercise that they're doing there varying opinions on that but certainly the type of exercise U and the amount can vary when people are pregnant but if you're seeking to conceive getting enough exercise is good because it's good for the mitochondria the mitochondria are present in that mid region of the sperm and mitochondria are critical for chromosomal segregation and the spindle and other aspects of the formation of a health healthy egg ovulation and fertilization in the female one thing that I know a lot of people are interested in nowadays is so-called intermittent fasting or time-restricted feeding me let's be fair everybody is restricting their feeding time because hopefully everybody is sleeping at some point in the 24-hour cycle and nobody's eating while they are sleeping that said many people are employing a so-called 8 Hour feeding window or a 10-hour feeding window or a 12-hour feeding window and indeed there are some data to support the idea that that can be a good thing for a number of different bi ological and health parameters however also a lot of data especially recently pointing to the fact that your overall number of calories and the quality of your food sources is going to be the most important variable and some people will simply find that time-restricted feeding intermittent fasting as it's also called is just a convenient way to ensure that your total intake of calories is not excessive for what you need now with all that said there is evidence that I've covered in a Solo episode and we'll soon have an expert guest on showing that time-restricted feeding can have certain positive outcomes for various aspects of organ Cellar and tissue Health okay this is somewhat controversial but there is growing evidence that by restricting your feeding window to say eight hours or 10 hours or 12 hours that it is better than if you were to eat over a longer period of um each 24-hour cycle but again the data are still incoming the reason we want to talk about time-restricted feeding intermittent fasting is that a lot of people do use it because they find it easier to not eat at certain periods of their 24-hour cycle than to restrict calories but again keep in mind you have to restrict calories if your goal is to maintain or lose weight all right a discussion that we've covered in that episode on intermittent fasting and in the episode with Dr Lane Norton and that we will cover in other episodes uh in the future so refer to those episodes at hubman lab.com if you would like to learn more about intermittent fasting per se for sake of this conversation a number of people are probably asking if I restrict my feeding to a certain window each 24 hours because that's what's convenient or because I'm excited about the potential positive effects of intermittent fasting is that going to disrupt the likelihood of fertility and thereby a healthy pregnancy and the short answer to that is if you are a female and you are having regular menstrual cycles that is a fairly consistent duration so maybe it's 21 days maybe it's 35 or anywhere in between but it's fairly consistent from month to month and you are following intermittent fasting Tim restricted feeding well then chances are pretty good that it's not disrupting your fertility and likelihood of fertilization in a healthy pregnancy of course during pregnancy you need to talk to your doctor and make sure that you're eating in a way that's supportive both of you and of the developing fetus that's extremely important I not aware of data exploring in a regimented way Tim restricted feeding during pregnancy okay so please please please if you're pregnant do not jump on a Time restricted feeding so-call intermittent fasting diet talk to your OBGYN talk to your your doctor talk to multiple doctors for that matter um before doing anything like that because of course you're now eating for two or if you have twins in there you're eating for three and very important if however you're not yet pregnant and you want to be fertile get pregnant or simply maintain a fertile potential and biology and you're following intermittent fasting it's going to be the regularity of those periods and regularity of cycle length it will tell you whether or not that's a good idea or not keeping in mind of course that if your total number of calories is too low your periods will cease that's a well-known effect but of course stress can also induce cessation of menstration and there are other factors that can induce cessation of menstration as well some of them start with changes in the brain literally in the hypothalamus some occur in the pituitary many of Lifestyle factors can do that but most typically it's going to be excessive caloric restriction or it's going to be a caloric deficit brought on by E excess physical activity so even if someone's eating a lot if they're not eating enough to offset their physical activity or they're not eating enough of in particular fats you know the essential fatty acids and protein but also carbohydrates well then menstration can cease and of course if menstration is ceasing chances are almost with certainty that you're not getting regular ovulations now in terms of male and whether or not intermittent fasting is going to disrupt spermatogenesis and testosterone production uh there there's essentially no data we can look to but we can look to the general logic around the relationship between body fat testosterone and spermatogenesis and this was something that was covered in a discussion I had on optimization of Hormone Health for males that I had with Dr Kyle Gillette who's a medical doctor and an obesity specialist again you can find that episode at hubman lab.com if you want to learn all about hormone opposition in males and essentially the story is as follows if a male is excessively overweight he's carrying too much body fat in particular not too much muscle although that can be an issue too but too much body fat is typically the issue so you know more than say 20% body fat well then losing body fat is going to be the primary goal for maximizing testosterone sperm health and spermatogenesis if however a male is already lean well then actually increasing calories will increase testosterone so it's a bit of a of a complicated story although not so complicated that none of us can understand it basically if you're overweight you should focus on losing weight in order to maximize sperm quality and health if you are very lean well then restricting your calories to the point where you are starting to lose weight or you're dropping even more body fat is unlikely to increase your testosterone further right doesn't necessarily mean it's bad or that you shouldn't try and go for for instance from 15% to 10% body fat I'm not saying that that's bad and that will reduce your testosterone but in general if you're already very lean so you know 10% body fat 5% body fat and you start restricting calories further your testosterone levels will drop so in the context of intermittent fasting it's really not an issue of whether or not your feeding window is 8 hours or 12 hours it's really an issue of whether or not you're getting enough calories to offset the physical demands and activities of your life whether or not you're on a maintenance diet to maintain your weight and of course you have to put all that in the context of whether or not you're overweight or lean to begin with the simple thing to take away from this is if you're a male who's using because you like it intermittent fasting SOC called time restricted feeding and you're following an eight hour or maybe even a one meal per day type approach although I don't really recommend that for a number of reasons we could talk about separately if you're eating over the course of eight or 10 or 12 hours hours per day because that's what works for you and you are ingesting enough calories to maintain your weight if you're already lean or you are ingesting fewer calories than you are burning in order to lose weight because you are already overweight and you want to lose body fat you're probably optimizing for all the things that you need to do in order to improve sperm quality and testosterone levels now also in that episode that I did with Dr Kyle Gillette on optimizing hormones for males we talked about testosterone replacement therapy it's not a topic I want to get into in any detail right now but I will say this remember earlier when we were talking about spermatogenesis and the fact that in order for sperm to be generated consistently every month ongoing from the time of puberty until essentially the time that a man dies you need two things you need testosterone production from the litig cells of the testes and you need spermatogenesis to be supported by that Androgen binding protein coming from the support cells from the CI cells so you need testosterone and you need Androgen binding protein and you need the litic cells and the CI cells active when men take exogenous meaning from outside the body testosterone either by cream or by patch or by pellets or more typically by injection the most typical trt approach nowadays is testosterone cenate which is biologically identical to the kind of testosterone you would make well because of negative feedback loops which you also learned about earlier the testicles themselves shut down their own testosterone production why would that be okay so you're taking testosterone in by syring or by patch or um any other method so the circulating testosterone and the amount that arrives at the test is going to be hopefully clinically appropriate not super physiological but it'll be somewhere in the healthy reference range maybe a little bit higher um nowadays some people are going a little bit higher so we're not talking about full-blown quote unquote anabolic steroid use keeping in mind of course that estrogen is a steroid testosterone is a steroid but when we think about steroids we mean like performance enhancing drugs so super physiological doses we're talking about within physiological or or near physiological ranges so if someone's in taking their testosterone in from an outside exogenous source the levels of circulating testosterone will be sufficiently high that the pituitary will register that and will stop making luteinizing hormone and generally follicle stimulating hormone as well and as a consequence spermatogenesis is vastly reduced or eliminated in other words for men who are on trt or who are taking testosterone from an external Source the number of sperm that they're going to make is going to be dramatically reduced there are things that they can do to at that like taking HCG human chonic anatropin which is just kind of a mimic for luteinizing hormone to stimulate the testes to continue to make testosterone and some men will also or instead take FSH to stimulate the CI cells to support spat spermatogenesis excuse me or both or some combination some people take chopine Clomid there are any number of different ways to bypass or offset the sperm reducing effects of taking exogenous testost this is a conversation that was covered in a fair amount of detail in that episode with Dr Gillette but just keep in mind that if you are taking testosterone from an exogenous Source your sperm counts will dramatically be reduced unless you do something to offset it so if you are wishing to conceive you need to think about whether or not you're going to offset the testosterone replacement therapy or whether or not you're going to come off it entirely so you'll need to talk to a urologist and a chronologist about that um and again a number of these different themes and way ways to go about tapering off trt were covered in that episode with Dr Kyle gallette so if you're on trt or you're considering taking it and you're interested in having children not just now but at any point you really want to take these things into consideration now I do want to point out that for the number of you out there who are taking supplements some of which we've talked about on this podcast I've talked about on other podcasts such as Tonga Ali turns out that there are a lot of men and women taking Tonga Ali to reduce sex hormone binding globulin levels to increase testosterone and estrogen in some cases libido and so forth those approaches meaning supplement based approaches to increase testosterone or free testosterone or some related hormones are not going to shut down your own endogenous testosterone production and reduce the number of sperm that you make or at least as far as we know disrupt ovulation in any kind of way provided that the dosages are within normal ranges again supplementation to support your hormones should not disrupt ovulation or sper metagenesis or testosterone production quite the opposite it should enhance it what I just described around trt is taking exogenous testosterone and that it's self is an entirely different Beast now with all of that said there are some supplements out there that include testosterone as a ingredient that's been snuck in to various formulas that include Blends and things of that sort you want to be aware of that and we did an episode about how to develop a rational guide to supplementation I highly recommend listening to that episode um again it's timestamped available free at huberman lab.com in all formats because it talks about which supplements are likely to be clean quote unquote to contain the things that you expect them to contain there's more and more evidence coming out that a lot of supplements including some um for instance uh supplements that contain testicle or the extracts of testicles can contain testosterone whether or not that can shut down your own endogenous testosterone production isn't clear no one's really explored that in detail but based on everything we just talked about with trt it stands to reason it might either reduce it or shut it down it's just never been explored yet so by all means make sure that you know what you're taking if you're taking supplements but again the major Point here is that for both females and males taking supplements to support healthy hormone production including things like Tonga Ali is not the same as taking hormones or bioidentical hormones which indeed can shut down your own endogenous production of hormones and thereby reduce both egg quality and the chance of fertilizing ation and healthy pregnancy and sperm quality and the chance of fertilization and healthy pregnancy anytime there's a discussion about fertility and pregnancy there seems to also be a parallel discussion about sex determination that is what factors can influence whether or not the child that's born is male or female that is whether or not it has double X chromosomes so One X chromosome from Mom One X chromosome from dad because the egg was fertilized by a sperm that had an x sex chromosome that 23rd chromosome or whether whether or not The Offspring is male whether or not has the X chromosome for Mom because it's always going to be the X chromosome in that egg and a y chromosome from the sperm that fertiliz that particular egg now of course there are instances out there of people that have xxy chromosomes or X Y Y chromosomes but the vast majority of people out there are going to have either an XX chromosome so we call that a female kot type right this is different than genotype and type but a female kype would be XX or a male kype which would be XY okay now despite the fact that it is the egg and the sperm and the chromosomes that they carry that are going to determine the chromosomes there's a lot of lore and discussion about the factors that can bias which sperm will fertilize the egg and thereby whether or not you're going to get an XX female or an XY male chromosome and therefore Offspring now not only is the lower around this whole issue of sex determination uh rather prominent but it is also somewhat unusual and um perhaps even interesting so for instance Aristotle himself proposed that if a man is thinking about himself and his own pleasure more than his partner and her pleasure at the point of ejaculation then The Offspring will be male Aristotle also asserted that if a man is thinking more about his partner and her pleasure at the point in which he ejaculates well then The Offspring would be female of course we have zero reason to believe that there's any truth to Aristotle's theory there are no data to support that in fact I'm not even sure how you would run that experiment because you can't really look at people's thoughts you'd have to rely on uh honest self-report and um even if people were to Faithfully report what they were thinking about uh at the moment of ejaculation this would involve of course bringing people into the laboratory and somehow um measuring or analyzing their thoughts or gathering their thoughts during the um sexual intercourse at the point of ejaculation then figuring out which uh biological sex was The Offspring Etc um just a near impossible and um probably not the most important experiment uh to invest our time doing nonetheless there continues to be a lot of lore about what determines the sex of The Offspring most notably there's a lot of lore in discussion and rumor about the idea that particular sexual positions at the point of a ulation during intercourse can somehow bias the likelihood that a pregnancy will be either resulting in male or female Offspring now again there are zero data to support this and yet this whole notion of sex determination is a really interesting one that people seem to be somewhat obsessed by so much so that again if you go online or if you were to talk to people in the sort of uh let's call it holistic or peripheral um Health spaces related to fertility there there is discussion about okay well you take this sexual position at the point of ejaculation to get a boy and you take that sexual position at the point of ejaculation to get a girl or you do um you do this in the early part of the day or the later part of the day again all for which there is zero data to support any kind of systematic relationship between what I just discussed and the biological sex of The Offspring that said there are now emerging methods that people are using in order to separate out the sperm that will indeed give rise to a male offspring versus a female Offspring now this of course is done in the context of invitro fertilization we haven't talked too much about invitro fertilization but invitro fertilization involves as the name suggests taking an egg and taking a sperm pairing them in a dish this can be done a number of different ways um but just to briefly describe the IVF um procedure IVF involves administering Supra meaning greater than normal Supra physiological levels of follicle stimulating hormone and luteinizing hormone during the follicular phase of a woman's cycle what that causes is the maturation of not just one egg that would be ovulated but multiple follicles and eggs and then ovulation itself is suppressed also through the administration of exogenous hormones and then under ultrasound guidance and OBG Wayan goes in and collects the mature eggs and follicles puts them in a dish and then sperm are delivered to that dish and those could either be sperm that were frozen previously or more typically or ideally it would be live sperm collected that day that are um washed through a very uh straightforward procedure and then those sperm either are allowed to compete for those eggs and fertilize those eggs and allow them to advance to um very early embryo stage before those embryos are frozen and eventually implanted into a woman in order to have them be carried to full term ideally or there's a procedure in which specific sperm are selected because they have the best morphology motility and so forth and in a process called iie I CSI in which the sperm themselves are literally forced to fertilize that particular egg now under those conditions typically a couple or a woman if she's doing this on her own with a sperm donor will get multiple fertilized embryos okay okay that are carried to a multi multicellular stage so that it's clear that they could grow into a child if they were implanted into a viable host uh sometimes the surrogate sometimes the woman who wants the child herself and under those conditions it is possible to look at the genetic makeup including the kype of those early nent embryos in which case people really can select the sex of their offspring that is they will have some embryos that are XX some EMB OS that are XY it's very likely also that they will have some embryos that have kyp or genotypes which are not ideal in that they would potentially lead to a miscarriage or some other genetic defect and so typically people do not select to implant those embryos if they have the option to implant embryos that are of either XX or XY kot type and the normal chromosomal um arrangements for obvious reasons so the the whole point here is that sex selection is possible but only using invitro fertilization the other thing that is becoming clear to us in more recent years is that sex selection is actually possible at the level of the sperm even prior to fertilization this is an emerging data set and this is largely happening in clinics outside of the United States but there are some clinics that have figured out methods in which they can take a sperm sample and they can spin that sperm sample in a centerfuse at a rate that separates out the sperm into what are called different fractions so for those of you done a little bit of biology with Center Fugees when you spin any kind of substance that includes multiple things in it of different weights when you spin them the things of different weights segregate out into different fractions along the depth of the tube and then you can take out one fraction or the next simply with a little pipet you take out the top fraction the middle fraction and so forth and what these clinics have figured out is that if they spin the sperm sample at the correct spin rate that the sperm that will give rise to male offspring and the sperm that will give rise to female Offspring segregate out into different fractions allowing them to take each of those fractions separately and to apply them to eggs if it's invitro fertilization and give rise very reliably certainly much more than chance to either male or female embryos they also of course can choose to do this outside the context of invitro fertilization so some people are now opting to have their sperm samples spun out in this way separate out the sperm that give rise to male or female Offspring and then to only use the fraction that they are interested in right so if they want a boy they'll use one fraction if they want a girl they'll use different fraction and then to use those fractions in the context of what's called IUI or intrauterine insemination which is as the name suggests rather than having the man deliver the ejaculate with his penis and the sperm with his penis they have a device you know the devices are now commercially sold believe it or not they're sold over the counter and on the internet so people will even do this at home and so what they're doing is they'll take the the sperm and they'll do IUI in order to bias the probability that they're going to get a male or a female Offspring again this is something that's now emerging um it's not common place most of the time people uh simply roll the dice as it as it were um by having either um intercourse and just hoping for or or not caring if they get a male or female Offspring um or in the instance of IVF selecting male or female Offspring sometimes largely on the basis of the chromosomal arrangements so of course um some people might prefer to have one or the other biological sex as their offspring but of course the healthy chromosomal arrangements are going to be Paramount for getting a healthy child and um as I mentioned before unhealthy chromosomal arrangements or abnormal chromosomal Arrangements often lead to miscarriage or Endor birth defects so selecting for healthy chromosomal Arrangements is always Paramount but some people are selecting for biological sex and indeed some couples who can conceive naturally are opting for IUI in order to be able to select biological sex because of this ability to spin out the sperm samples to um different fractions and select the male or female sperm that is the the sperm that would give rise to a male or female Offspring so this is a uh rapidly emerging theme believe it or not um who knew um and of course it has nothing to do with Aristotle's assertions about what people are thinking about at the point of ejaculation nor does it have anything to do with body position at the point of ejaculation but I do find it rather interesting that um even in this day and age people uh seem to be continually pursuing new and different ways to understand why one sperm or another sperm happens to uh fertilize the egg and when that information is not available because frankly it's not available yet we don't know why a sperm containing a y chromosome or a sperm containing an X chromosome is more likely to fertilize an egg andan there's some ideas for instance that older fathers tend to have more daughters as opposed to Sons but when you really look at the data it's pretty mixed so if you've heard that um before um has a particular nickname that I'm I'm not going to describe on the podcast you can look it up online but um if any of you are aware of any other uh kind of ideas or lore no matter how ridiculous or crazy um please put them in the comment section on YouTube I'd be very curious to learn about uh those mostly out of um uh interest and curiosity but look sometimes these outrageous stories such as uh Notions of body position and what how they influence biological sex even though they turn out not to be true turn out to be interesting for other reasons and in fact next we're going to talk about how body position during sexual intercourse can in fact influence fertility and pregnancy so another common theme around fertility and pregnancy that you'll hear about is that for couples that are trying to get pregnant that during intercourse they should do whatever it is that works for them but then after the man ejaculates that the woman should try and position her ankles above her head or somehow otherwise tilt her pelvis back in order to increase the rate Andor probability that the sperm swim toward the egg as opposed to the other direction now I talked to a couple of different OBGYNs and urologists that are focused on fertility about this topic and it turns out you get pretty mixed answers as to whether or not there's any validity to this idea that the woman's body position after the man ejaculates inside of her can somehow influence the probability of pregnancy one group of experts told me that there is no reason for a woman to need to continue to lie down Elevate the ankles or in any way tilt her pelvis back in order to increase the probability of successful fertilization the other group suggested that indeed there is a strong reason to believe that tilting the pelvis back maybe even keeping the ankles elevated and having a woman lie on her back for about 15 minutes with the pelvis positioned at about 20° back is ideal for optimizing fertilization I mean they were really specific about the recommendation so I find this interesting that within the uh cohort of extremely well-trained MDS so OBGYNs and Urology fertility docks and gyns you see a split it has nothing to do with whether or not the um the physician was male or female uh or their training or their institution none of that there just seemed to be a sort of even split between the two now granted it wasn't the largest sample size that I could have obtained and yet I do find it interesting that there's this um this split in the opinion about this one group the group that said no pelvic position doesn't really matter um don't worry about it it's not going to influence uh the rates of fertilization argue that the sperm swim very quickly and that if they are released near the cervix they're going to swim very quickly toward the egg in order to fertilize it regardless of pelvic position the other group said well yes sperm swim quickly and even if they're released right at the entry to the cervix that the sperm still have a long distance to go again if you were to scale this uh according to the size of the sperm versus the size of a human body an entire human body what you'd um scale it to is the distance between Los Angeles and San Francisco and it needs to undergo that basically within 24 hours or so although as we mentioned earlier sperm can survive quite a while inside of the woman's body maybe three or five days at least so in both cases they acknowledge it's a long distance but on the one hand you have a group of experts that are saying the sperm more or less know what to do and are going to do it regardless of the position of the woman after ejaculation inside her and the other group saying no we want to do everything we can to bias the likelihood that the sperm will fertilize the egg okay right well setting aside the basic argument that tilting back of the pelvis and lying stationary or so for about 15 minutes after sexual intercourse and ejaculation is not a um an expensive uh you know Endeavor although it requires a little bit of time um and it forces people to remain motionless or or close to motionless and they're not up up and around and moving about aside from that it's a relatively low investment so one argument is well if it could bias the likelihood of fertilization at all and people want to get pregnant why wouldn't they do that okay so that's a reasonable argument but it doesn't really point to the mechanism the arguments that point to a potential mechanism are that if you recall what we were talking about when we talked about sperm quality sperm quality involves a bunch of different measures like concentration of sperm per milliliter seen um morphology of those sperm how many are forward motile it turns out that in any one ejaculate sample the total number of forward motile and yet fast forward motile sperm that are also of the highest quality morphology is actually quite low and so the idea here is that you want to get as many sperm of the highest quality swimming toward the egg because those sperms stand the highest probability of fertilizing that egg and in fact this relates to some of the discussion we were having earlier about behavioral dos and don't for sake of increasing the probability of fertilization and the one that is most important here is cannabis turns out that the data on cannabis really do support the idea that some of you may have heard from um parents and teachers I don't know I did hear this from uh parents and teachers that um cannabis can disrupt the swimming styles of sperm in in ways that are not supportive of fertilization that it can turn more of the sperm into twitchers although when I learned about this I was not informed of the word twitchers what I was told is that if you use cannabis that the sperm don't know which direction to go that they're confused um almost sort implying that the the sperm themselves are are high on cannabis well that's certainly not the argument that I'm making here but it does seem to be the case that people who use cannabis even once the sperm that are generated during that particular month or two months during which or after which they use cannabis have less forward motility and possibly altered morphology as well okay I want to be very clear I did not say that if you use cannabis once you are forever disrupting the motility and morphology of your sperm I did not say that what I said is that if you use cannabis once then the sperm that are generated in the 60 days after that cannabis use are going to have a higher incidence of disrupted motility and perhaps morphology as well okay remember sperm continually generated every 60 days or so and so if you use cannabis once you are not forever disrupting your sperm but if you are using cannabis and then you are looking to conceive in the next 60 days you are going to be reducing we think significantly so the number of quality forwardly motile sperm so the simple takeaway from this is avoid cannabis use although if you are going to use cannabis and again there are medical uses of cannabis and beneficial uses of cannabis for for certain populations it can be bad for other populations we talked about that in the hubman lab podcast all about cannabis but if you're going to use cannabis you should try and abstain from Cannabis in the two months prior to the attempt to fertilize and get pregnant now I'm not aware of any data on how cannabis use by the woman can influence the likelihood of fertilization in pregnancy and I want to couch this whole discussion around cannabis Under the Umbrella of something that came up in the episode that I did on cannabis which is that for about half of people out there male and female okay so here we're not distinguishing um by biological sex about half of people that use cannabis report it as an aphrodesiac it makes them want to have sexual intercourse more than if they don't use cannabis and for the other half it actually has the opposite effect by way of an influence on a hormone called prolactin which suppresses the dopamine system the testosterone and the estrogenic system and so this whole idea that cannabis is an aphrodesiac seems to be true for about half of the human population and not for the other half of the human population so I mentioned that because I know a number of people uh use cannabis as an aphrodesiac they like to use cannabis before intercourse it was actually um very surprising to me to discover when I researched that cannabis episode that approximately 155% of women who are pregnant continue to use cannabis during pregnancy and that's a very alarming statistic and everything we know is that the use of cannabis during pregnancy is detrimental to the health in particular the brain development of the fetus so that's a real concern I highly recommend women abstain from cannabis use during pregnancy um talk to your OBGYN about it if you're using it all or considering using it all so based on what I told you earlier about the fact that cannabis use is not good for egg quality and the fact that cannabis use can disrupt the motility of sperm and therefore is not good for sperm quality and it can disrupt the patterns of swimming in sperm in ways that reduce the likelihood of fertility I think the take-home message is clear which is that whether or not um you want to be a cannabis user or not if you are going to try and conceive and certainly while you're pregnant you're going to want to avoid the use of cannabis and that is smoked cannabis and Vaped cannabis and during pregnancy the consumption of cannabis even in edible form or in tincture form is also going to be detrimental to the developing fetus but of course we started this conversation in the context of body position in particular at the point of ejaculation in determining the sex of The Offspring Andor the likelyhood of getting a successful Fertilization in pregnancy and I think that given that the tilting back of the pelvis so again this is elevating the pelvis by about 20° I don't think it has to be exact exact but about 20 Dees for about 15 minutes post ejaculation inside of the the woman or I suppose if people are using IUI intrauterine insemination since that seems to be the consensus among those experts that believe that pelvic tilt backward can be beneficial for increasing the probability of fertilization and given that it involves no cost but a little bit of time seems to me that if you want to get pregnant that that would be the right thing to do and as far as I know there's no information nor was I able to obtain any recommendations from experts about what the ideal body position of the male is after ejaculation if the goal is to increase the probability of fertilization in pregnancy so we've been talking about behavioral interventions some dos and some don'ts that people can do to increase their fertility and the likelihood that any fertilized egg will be carried to terms successfully and soon we'll also talk about things that people can take to improve their fertility now keep in mind that this entire discussion is about fertility but also remember as we discussed at the beginning of the episode trying to increase your fertility is one of the best ways to think about trying to create and maintain optimal physical health so for people that are trying to conceive and for people who are not trying to conceive optimizing your fertility status whether not you're male or female it's one of the best ways to Target those approaches and there are now a lot of data supporting the idea that Acupuncture of all things can be very beneficial for improving both female and male fertility and should a woman get pregnant for improving the quality of outcomes that is the likelihood that there there will be a successful pregnancy that is carried to term not premature and so on and so forth now for some of you out there you might think oh of course acupuncture acupuncture has been known to work for thousands of years and therefore it's not surprising that it would assist with fertility in pregnancy for many of you out there however probably thinking acupuncture that seems kind of like fringe science but what I can assure you is that there are now quite a few clinical trials funded by government agencies like the national instit udes of Health showing that acupuncture is a very effective treatment for a number of different things including fertility and pregnancy but for hormone status for stress relief but even for chronic illnesses of different kinds including autoimmune illnesses so this is no longer considered fringe science in fact one of the best Laboratories in the world working on this is a laboratory out of Harvard Medical School run by a guy named chuu ma chuu's lab has really been exploring in a mechanistic way how the different stimulation sites that are used in acupuncture so where the needles are inserted tap into neural Pathways that link the different organs of the body so for instance they've found that stimulation of a particular site on the lower limb can reduce inflammation dramatically throughout the body by way of neural Pathways that originate in the lower limb and extend to areas such as the kidney and the pancreas so all these um quote unquote ancient maps of the human body as they relate to acupuncture are now being parsed at the level of mechanism which I think is wonderful because it not only is showing us that so much of what has been purported and reported in the landscape of acupuncture actually has an underlying mechanistic basis and with additional mechanistic understanding of course always arrive new and better practices that's the idea to evolve these fields of acupuncture to evolve the fields of mechanistic understanding of our biology and health and so the issue of whether or not acupuncture can assist in getting pregnant and in carrying a child to term and for that child to be healthy uh are really starting to emerge uh in a major way and uh rather than go into all those data in detail what I can tell you is that there are clinical trials and data supporting the fact that female fertility itself can be supported by acupuncture through several mechanisms one of which is the balancing and I realize that's a somewhat tricky term and I'll Define it better in a moment the balancing of hormones across the ovulatory SL menstral cycle including regulating levels of FSH so that they're not too high nor too low and restricting the FSH to the follicular phase of the of the menstrual cycle as well as using acupuncture to improve things like blood flow and the health of the ovary itself and other aspects of the female reproductive axis so acupuncture can operate at the chemical level impacting hormones it can act at the mechanical level impacting the different tissues through which the egg has to pass and so on and so forth likewise on the male side acupuncture has been shown to improve seamen volume quality of sperm sperm motility Etc and in large part through changes in the neural Pathways that inate the very tissues and Vascular input to the scrotum and testicles because as we learned earlier temperature regulation of the scrotum and testicles is so vital for getting healthy sperm and increasing sperm quality in addition there are good data to support the idea that acupuncture can increase levels of testosterone free testosterone and the sorts of hormones that are going to support healthy hormone production and sperm production in males and this is distinct from applying testosterone from an exogenous Source right so when we're talking about acupuncture and increasing levels of testosterone we're talking about increasing levels of endogenous testosterone so those leig cells can support the CI cells and the CI cells can make that Androgen binding protein and you get enhanced spermatogenesis you can find evidence for all of these different features both changes to the chemical milu that is the hormones and changes to the mechanical milu including for instance Improvement of the pathways leading from the seminiferous tubules to the epidemis to the vast Defence basically clearing out the plumbing so that more quality ejaculate can be delivered which of course is going to increase the probability of fertilization so when you hear that acupuncture can improve the likelihood of pregnancy um that's an accurate statement for which there are now increasing amounts of mechanistic data if you want to learn more about how acupuncture can be used to contribute to improved fertilization and pregnancy there are a number of different excellent reviews on this um both as it relates to females and as it relates to males um one of the best papers that I happen to like is one that we'll provide a link to in the references entitled acupuncture and herbal medicine for female fertility and overview of systematic reviews so a review a review of reviews this was published recently in um 2021 we'll provide a link to that and um there's also going to be a link to a review that relates to acupuncture for male fertility and hormone augmentation I should just mention briefly that if you're going to look at scientific papers one thing that you want to consider is also looking at the references that they reference now of course papers tend to reference a ton of references in particular in reviews so what you want to do is look for the references that are showing up most often in the introduction those references often are going to be the most prominent recent reviews or the most important findings in recent years that's not always the case but that's often the case so if you read the first couple of paragraphs of these papers and these are openly available as full full text by the way online if you go to these links you'll be able to access the best papers the most relevant papers in the context of acupuncture supporting female and acupuncture supporting male fertility and hormone status now I'd like to discuss things that both men and women can take in order to maximize their fertility and again and again when we're talking about fertility we're talking about people who want to conceive and have children but also we're talking about a basic measure of overall health status so if you're somebody who does not want to conceive children I still encourage you to think about whether or not you would want to do certain things or not do certain things in order to maximize your fertility as a means to maximize Your vitality and Longevity because that's really what maximizing fertility is about for a lot of people that said I know a lot of people would like to conceive children perhaps not right away but in the future and what I'm about to describe are some tools and interventions that is things that one can take in order to improve their hormone status but also in particular the quality of their eggs and the quality of their sperm in the short and long term the first on the list of things that people can take in order to improve egg quality or sperm quality is ELC carnitine ELC carnitine is present in various Foods in particular in red meats but again it's going to be very hard to get sufficient levels of el carnitine to improve egg quality and sperm qual the unless you're going to take it in supplement form the typical recommendation based on peer-reviewed studies that have shown significant improvements in egg quality that is chromosomal Arrangements that is the likelihood of fertility or pregnancy rather the likelihood of sperm being forward fast swimmers as opposed to twitchers or REM motile and having proper morphology all those measures has been demonstrated to be significantly improved by the ingestion of ALC carnitine how much ELC carnitine well that depends on how you're obtaining the ELC carnitine if you're obtaining it in capsule form 1 to three grams per day of capsule form ALC carnitine is what's been suggested to improve egg quality and sperm quality Now 1 to three grams per day can be taken all at once or spread out throughout the 24hour cycle it can be taken with or without food does not seem to matter and when taken for a period of 30 to 60 days does seem to significantly improve all the parameters that have been discussed for egg quality and sperm quality now the mechanism for that effect is pretty clear ELC carnitine is involved in the processing of lipids fat in terms of mitochondrial function and as we talked about before mitochondria are vital for the organization and action of the spindle that pulls apart the chromosomes taking that cell within the female from diploid to haid which is essential you really want just the 23 individual chromosomal strands you don't want chromosomal repeats it's also involved in the actual Fusion of the egg as it exits the ovary and enters the ovulation cycle mitochondria are also important as we talked about before for the forward motility of sperm because of the enrichment of mitochondria in that mid region just behind the head that caus the whipping uh flagellation of of the tail allowing for forward movement as well as other aspects of Cellar more morphology so it makes a lot of sense as to why ELC carnine supplementation would be beneficial again it's 1 to three gram per day over a period of about 30 to 60 months if you're hoping to conceive in the upcoming months recommend taking it for at least 30 days prior to that um of course based on the data we talked about before cumulative probability fundability Etc there's no reason to not continue to try for pregnancy before taking El quarantine but El karantine is going to improve egg and sperm quality and so you might actually take the stance that even if you don't have any problem getting pregnant wouldn't you want to maximize the quality of the egg that gets fertilized and the quality of the sperm that fertilizes that egg so that's additional rationale for taking ELC carnitine one important note if you are going to take ELC cartine in oral form in capsule form it can increase something called tmao tmao can cause stiffening of the arteries you don't want tmao levels to go too high one way to offset the increases in tmao caused by Oral elcar is to take 600 Mig of garlic per day um you I suppose you could eat cloves of garlic that would work just as well because garlic contains something called Allison which can offset the increase in tmao but 600 milligram capsules of garlic are going to be or garlic extract rather is going to be the most uh probably cost-effective and um simplest way to do this um and also they areen going to create that garlic smell some people like the smell of garlic some people don't so if you're going to take oral Al carnitine I suggest also taking 600 Mig a day of garlic extract and you can do that at any time throughout the day it doesn't have to be with the alc carnitine the next item on the list of compounds that have been shown to improve egg quality and sperm quality and quite robustly so is co-enzyme Q10 co-enzyme Q10 is something that you can actually measure levels of in your blood most Physicians will say that they want to see your levels of co-enzyme Q10 to be somewhere between 0.5 and 2.5 it's going to depend on the units most people I realize they not going to run off and get their Coq 10 measured um it's not included in most standard blood tests but if you were to measure your CoQ10 that's the range that you want to look for that said many people opt to supplement with CoQ10 and you'll find that many fertility docs OBGYNs and urologists that are trying to assist their male patients with fertility will suggest CoQ10 because again it supports the health of mitochondria mitochondria is so vital to so many aspects of the formation and fertilization of the egg and sperm that of course fertilizes the egg the co-enzyme Q10 dosages that are most often suggested and that you'll observe in the peer-reviewed research literature on humans I should add is 100 to 400 milligrams per day and the co-enzyme Q10 is taken generally with a meal and ideally a meal that contains fat and there's even some idea that taking co-enzyme Q10 with your dinner assuming that dinner includes some fat you don't have to add additional fat is going going to be more advantageous than taking co-enzyme Q10 early in the day although that's probably a detail that's getting a little too far down in the weed so again 100 to 400 milligrams of coenzyme Q10 per day whether or not you're a man or a woman for improving the likelihood of fertility by way of improving egg and sperm quality and again if you're somebody who just doesn't have any problem getting pregnant or if you're already producing many sperm of quality morphology this is another case in which you could take a step back and you say well why wouldn't I want to further optimize the quality of the egg in the sperm because the quality of the egg and the sperm ultimately are going to determine not just whether or not you have a successful pregnancy but are going to determine admittedly in ways that will forever remain cryptic to you but nonetheless are going to be important in determining the qualities of the brain tissue and body tissue of your Offspring the third item on the list of compounds which are commonly suggested or prescribed by fertility docs nowadays for men and women wishing to conceive Andor optimize their fertility as a basis for General vitality and health is inositol now inositol has many uses so you'll hear about the use of inositol for reducing anxiety or improving mood or even for the treatment of depression we talked about inositol in previous episodes of this podcast um for instance I talked about inositol and in particular taking 900 milligrams of myoinositol prior to sleep which is something that I do along with the other supplements that I take and recommend for Sleep such as magnesium 3 and8 appenine and theine if you're curious about those you can see our newsletter on sleep or our perfect your sleep episode or the master your sleep episode talks about behavioral and supplementation based tools for improving sleep but myosl is not just suggested for or prescribed for people that are wishing to get pregnant and for General Health but myosl is often recommended for people that want to improve egg and sperm quality because of the way that it can positively impact insulin sensitivity insulin sensitivity might sound like a bad thing uh to people out there but it turns out that you want to be insulin sensitive the last thing you want is to be insulin insensitive insulin insensitivity is associated with type two diabetes with obesity and even for people who are not challenged with obesity you want your cells to be insulin sensitive you don't want a lot of insulin floating around in your system with your cells unable to use that insulin that's really what insulin insensitivity is about myoinositol at dosages of 1 to 5 gam per per day it's pretty high 1 to five grams per day keeping in mind that 1,000 milligrams is 1 gram has been suggested to improve egg quality and sperm quality now one point of um I wouldn't say caution but of note is that myosl can reduce anxiety and it can be a slight sedative which is why um some folks including myself take almost a gram 900 milligrams prior to sleep if you're going to take 5 grams of myosl you would want to restrict that to the late evening or second half of your your day and I don't suggest starting that high I would start with one or two grams and then working your way up seeing what you can tolerate um in terms of the level of uh anti-anxiety and drowsiness that it produces 1 to five grams per day of myoinositol is what's suggested for both men and women wishing to improve egg health and sperm Health but for women it's also often suggested to include also okay so that to take myosl but to also take deyro inositol deyro ocol has elements in it that can be both Pro and anti-androgenic androgens are things like testosterone and related molecules there are a number of different causes of infertility and disruption to egg quality age being the most significant factor but another significant and very common factor even among young women who are of fertile age is having too many androgens and as it relates to something called polycystic ovarian syndrome we'll do an entire episode about menopause and PCOS and a number of other things that relate to fertility because it's an entire and very interesting other discussion that we need to have but the recommendation is that women take 1 to five grams of myosl but also deyro andosol because of the ways that it can balance androgens and offset some of the negative effects of polycystic ovarian syndrome or even for women who do not have polycystic ovarian syndrome because of the ways that dcyo andosol can balance androgens in ways that are beneficial the dosages of deyro andosol that are recommended tend to be 125 to 140th of the myosl dose so you have to get out your calculator remember 1,000 milligrams equals 1 gram so figure out if you're taking one gram of myosl per day or two grams you're going to want to convert that to milligrams so let's say you're taking two gram of myosl per day that's 2,000 milligrams and you'd want to divide that by 25 and that's how many milligrams of deyro andosol you would want to take as well or you could go with the lower end dose and divide it by 40 and take that number of milligrams of deyro andosol along with the inositol again probably taking it later in the day is going to be good it's not clear at all that taking it with food or without food makes any difference whatsoever so I would suggest you do either keep in mind as I'm I'm discussing these recommendations I may call them prescriptions but none of these are prescription drugs and of course you should always discuss any supplements that you're planning to take or stop taking for that matter with your physician I don't say that to protect me I say that to protect you you know anytime you're going to add or change something in your overall health regimen you want to discuss that with your um trusted healthc care professional typically I would hope a board certified MD the fourth item in the list of commonly suggested supplements for men and women wishing to optimize egg and sperm quality respectively is omega-3 fatty acids and now here we're talking about something that could be obtained from food and can be obtained from food so if you're consuming fatty ocean fish things like uh sardines anchovies salmon with the skin chances are you're going to get some quality Omega-3s Omega-3s are also available in plant-based sources um it's also available in krill for that matter um but most people find it difficult to reach the threshold required for optimizing mental health and physical health that is the threshold of the EPA essential fatty acids and so for that matter I've suggested before in this podcast and many fertility docs will suggest that they patients take omega-3 fatty acids in supplement form it could be taken in liquid form or in capsule form but enough of those so that you're getting at least one gram per day of the EPA form of Omega-3s okay so at least one gram per day and as high as two or even three grams per day of the EPA form so you'll need to look at the packaging because often times it'll say high potency Omega-3s you'll it'll say um you know 1500 milligram of Omega-3s but that's not 150000 milligrams of the EPA form you look on the back a label and it'll say each serving contains 750 milligrams of EPA you want to get above that 1 gam dosage per day and as high as 3 gram per day of the epas the most cost-effective way to do that is going to be liquid form omegas but that's a little bit inconvenient for many people and some people don't like the taste that's why they rely on the capsule form omegas and of course there are compounds that can impact fertility status quality of eggs quality of sperm not by adjusting mitochondria or insulin sensitivity or creating a general millu of support for the egg and the sperm production and function such as the compounds that I just listed off to but rather compounds that influence the hormones involved in the generation of sperm and the generation of the eggs in involved in the ovulatory cycle and the spermatogenesis cycle that is now these are going to come in different forms and I want to just emphasize that the supplements that do this that adjust hormones in these ways that can be beneficial are distinct from hormone therapy or bioidentical hormones okay distinct from hormone therapy or bioidentical hormones because as we discussed earlier when you take a hormone like testosterone or even estrogen for that matter from an exogenous an outside Source you're going to disrupt the feedback Pathways inside of your body and you're going to shut down your own endogenous production the supplements I'm about to describe do not do that and yet can adjust levels of hormones in more subtle ways that could be beneficial for the process of maximizing fertility for males and for females the first of which on this list I'd like to discuss has been discussed in previous podcast as well which is a substance called tongat Ali Tonga Ali also goes by other names but when taken at 400 milligrams per day sometimes separated into two dosages but typically taken as once a day early in the day because it can be a little bit stimulating although not anxiety provoking I've never heard of that can be a little bit stimulating but 400 milligrams a day of Tonga Ali is has been shown to increase free testosterone by way of reducing something called sex hormone binding globulin it's also been shown to increase luteinizing hormone the net effect of which has been described as a subtle but significant increase in libido and some of the other parameters associated with increased androgens like free testosterone in males and females so a number of people out there are taking Tonga Ali in this way 400 milligrams per day restricted to the early part of the day with or without food people always ask do you need to cycle Tonga Ali I'm not aware of any need to cycle Tonga Ali in fact it tends to work better meaning the effects on libido and some other hormone profiles tends to increase over time again Tonga Ali is an option is certainly none of these things are requirements um we're simply listing off options but many people both males and females seem to benefit from and like Tonga Ali even if they're not seeking to conceive there's no reason to think that Tonga Ali directly improves EG or sperm quality except in males the increase in androgen created by tongat Ali supplementation can indeed lead to improved spermatogenesis so there's a growing amount of data in this research ler on Tonga Ali many people find it beneficial and so it's something that both men and women wishing to conceive Andor optimize their fertility just as a general Health parameter might want to explore the other supplement that's been shown to improve both egg quality and sperm quality and there I'm referring to a number of different parameters related to egg quality and sperm quality as well as to to increase libido fairly substantially is a substance called Sheila Sheila uh spelled Shi l a g t Sheila is actually a uh compound that's used in ayurvedic medicine but there's some really good research studies exploring the supplementation with shogy at about 250 milligrams twice per day and this has been looked at in males and in females and it does seem to significantly increase two hormones one is testosterone and the other is follicle stimulating hormone and for that reason shogy is often considered a tonic that people use both as an aphrodesiac uh to increase libido as well as to increase fertility now one note of caution if you're a woman and you're considering taking shogy in order to increase testosterone and follicle stimulating hormone keep in mind that the ovulatory cycle is this very tightly regulated cycle in which you want low but elevated of follicle stimulating hormone early in the follicular phase then it Peaks right before ovulation and then low levels of follicle stimulating hormone in the second half of your cycle for that reason using shogy chronically around the entire course of your ovulatory cycle could be a little bit risky and I'd recommend that you talk to your OBGYN um prior to doing that or if doing that at all for males it's a little bit less of an issue because as I mentioned earlier sperm are constantly being generated and the presence of FSH is going to increase spermatogenesis now Sheila G is not FSH itself Sheila G stimulates the release of FSH and it stimulates the release of testosterone so again there's no reason to think that it would shut down your endogenous testosterone or FSH production um although there are limited amount of data that really explored that in detail many people use shogy in order to increase their testosterone FSH their libido and various aspects of sperm health again the dosages of Sheila are about 250 milligrams two times per day one issue with Sheila G is it often comes as a as a tar was a little hard to measure out the dosages yes a tar it's this um kind of thick gummy substance that you're supposed to dissolve in water and the recommendations are you take a little bead and dissolve it in water it is available in capsule form where the ability to control the dosage is a little bit um is made a little bit easier but of course as with any supplement I recommend starting with the lowest possible dosage so you might want to start with a small very small bead of Sheila G dissolved in water taken once per day and then increase the dosage as needed in order to obtain the effects that you want things like shogy start to um bring us into the realm of uh what can only be described as a little bit unwieldy right here we're saying you can't really control the dosage now you're talking about hormones that need to be tightly regulated at least for females across the ovarian cycle for males yes it has been shown to increase testosterone and FSH improv sperm motility and sperm count pretty significantly no reason to think that you couldn't do that chronically with shogy and yet I do want to acknowledge that Sheila as this black tar substance is contains a lot of different things in fact it comes from a mineral pitch what is that it's like it comes from the literally the dirt and plants that have been compressed by rocks in the Himalayas so it's pretty esoteric stuff when it really comes down to it but the biological effects of shogy in both males and females seem to be related to the fact that it is highly enrich in something called fulvic acid and fulvic acid is involved in a lot of different cellular processes not the least of which at least in this context is the transport of molecules across cell membranes and for hormones to have their effect they need to cross cell membranes on the outside and the inside of the cell um so maybe that's how it's having its effect again the mechanisms of exactly how Sheila increases testosterone in FSH and thereby libido egg quality and sperm quality aren't entirely clear but for um the more adventurous of you out there who want to experiment with shogy whether or not you're trying to conceive or or not um it might be something to consider but of course do talk to your physician the next compound that I want to discuss is zinc and then this discussion mainly pertains to males although I um of course should point out that females should get the recommended daily allowance of zinc each day males on the other hand seem to benefit from having additionally high levels of zinc intake now that can be obtained through Foods you know you'll often hear oh you know oysters are enriched in zinc and and oysters are in aphrodesiac you know I don't know who's doing the marketing for oysters but it's it's really uh terrific I think that seems to have persisted and um and maybe it's true uh they are oysters are enriched in zinc what does zinc do for fertility well in males we know based on a really nice set of studies that zinc dosages that are pretty high of about 120 milligrams taken twice per day that's quite a lot with meals can significantly increase testosterone and dihydrotestosterone and this probably shouldn't come as a surprise to us it turns out that zinc is highly enriched in human testes and in the testes of other animals including fish and other mammals and it was actually in 1921 that it was observed in fish that zinc levels Skyrocket in the testes of fish during their breeding season so zinc is correlated with increases in breeding but you never know which direction that correlation is running turns out that zinc in both animals including fish other mammals and in humans strongly impact the enzymatic functions in the testes including the function of Androgen binding protein so it seems that high levels of zinc can increase spermatogenesis and testosterone levels very significantly this was explored in a really nice study that I'll provide a reference to it's an older study I really like it it's called effect of zinc Administration on plasma testosterone dihydrotestosterone and sperm count this is but just one study among um many now this dates back to 1981 but there have been uh studies subsequently that point to the fact that implementation with zinc at those high levels can really be uh helpful in terms of increasing sperm count testosterone and even testic size of all things so one important point about taking zinc this 120 milligrams of zinc two times daily um definitely needs to be done with meals if you've ever taken zinc on an empty stomach even if you just take 15 or 30 milligrams of zinc you can feel very nauseous not well for a few hours so make sure that you're taking zinc with full meal so this would mean that you're taking um in at least two full meals per day um I should also mention that zinc supplementation did not appear to impact gonadotropin releasing hormone or prolactin so it seems to be a fairly targeted effect on the testosterone and related Pathways in males as far as I know there have not been systematic explorations of the effects of high levels of zinc Administration on females I would hope that those studies would soon be done but meanwhile if you're a male and you're interested in improving sperm quality and your testosterone levels overall for whatever Reon reason zinc likely is a good candidate and that pretty much summarizes the compounds that men and women should take in order to maximize egg quality sperm quality and fertility and then of course we start to enter the landscape of other things that men and women can take in order to improve fertility and those other things generally are prescription drugs and so I just want to mention what a few of those are but of course these are things that you would absolutely have to obtain prescriptions for from your md and your md would without question would want to take blood tests prior to prescribing these things so for instance if men have been taking exogenous testosterone through the use of anabolic steroids like performance-enhancing drugs or even testosterone replacement therapy their endogenous testosterone levels are going to be very low and their sperm counts are going to be very low unless for instance they are prescribed and taking something like HCG human coron gonadotropin which mimics LH and would stimulate the testes to produce testosterone and through some indirect Pathways uh rest spermatogenesis although not to the same degree as if people are not taking exogenous sources of testosterone some men even if they've never touched trt or exogenous testosterone of any kind will be prescribed to take HCG because of its ability to stimulate the testes produce more testosterone and sperms they're just taking HCG alone other men will take or will be prescribed rather FSH in order to stimulate spermatogenesis or HCG and FSH or Chopin which can regulate all sorts of things in the both testosterone and estrogen related Pathways at the level of brain and pituitary and gonad testes likewise for women if they're low in FSH they might be prescribed FSH if they are um low in luteinizing hormone they might be prescribed HCG if they're low in testosterone they might even be prescribed testosterone and if their testosterone is too high and they're dealing with PCOS they might be prescribed anti-androgens and androgen blockers and on and on and on there are so many different hormones that can impact the different aspects of the ovulatory and the spermatogenesis cycle that the OBGYNs and the urologists focus on male fertility nowadays really have an excellent handle on which levers and buttons and threads to pull and push and and so forth in order to set in motion a proper ovulatory cycle and a proper spermatogenesis cycle you know everything we talked about up until now and in the early phase of this episode especially about how the brain commands the pituitary and the pituitary commands the gonads and then the gonads the ovary or the testes send feedback signals to the pituitary to then influence the pituitary all of that incredible orchestra that dance is so tightly regulated in a way that really provides the OBGYNs and the fertility docks concerned with male fertility exceptional tools to for instance figure out if a man is not producing any sperm but his testosterone levels are well within normal range well then there's some very clear sets of explorations and potential treatments some of which are mechanical making sure the epidemis and vast defin are clear allowing the sperm to enter the ejaculate and the ejaculate to enter the urethra and the obviously um to enter the female as well as for a woman who's not ovulating to adjust her levels of FSH or maybe even to apply acupuncture in conjunction with supplementation and various prescription hormone therapies to adjust fertility and ovulation and the probability of successful pregnancy so there's a vast land landcape of prescription drugs and surgical interventions of varying degrees of invasiveness and some are for instance outpatient procedures some require general anesthesia Etc in order to maximize male and female fertility what I've tried to do today is to provide you with a deep dive understanding of the ovulatory and menstrual cycle we talked about the brain the pituitary the ovary the Fallopian tubes and in fact the whole female reproductive AIS as it relates to to fertility and reproduction I also describe the male reproductive axis as it relates to the brain the pituitary the gonad the testes and the various ducts the pathways out of the testes that allow the sperm to be enriched within the seamen and then the seen and the ejaculate to exit through the urethra I did all that as a way to frame the various tools and interventions that can really assist in increasing fertility egg quality and sperm quality so when we discuss mitochondria in the context of the development of an egg where the development of sperm and its ability to swim quickly forward now it should make sense as to why a given intervention whether or not it's El carnitine or whether or not it's exercise or whether or not it's getting enough sleep and limiting stress why all that should matter and why in fact mechanistically those interventions can work because indeed there are many interventions that we can all do and use to support our fertility and again as a more General theme today I really really wanted to a teach you about the human reproductive axis I do find the biology of the ovulatory and menstrual cycle and spermatogenesis to be absolutely fascinating to me and again if you're somebody who's interested in conceiving or if you've already conceived children and even if you don't want more children this is really the aspect of our biology that allowed us to be here it's the aspect of our biology that determine whether or not we are male or female it's the aspect of our biology that determines so so much and yet I think that most most of us generally are not taught this in school or at least not at the depth that we discussed it today so hopefully that information was in and of itself interesting and perhaps useful as well and I do think that even if people are not wishing to conceive more children that the information related to fertility in optimizing egg and sperm health is a value in the sense that optimizing egg and sperm Health can be used as a proxy for optimizing our body and brain health generally in other words and here I'm admittedly taking uh words out of the mouths of the various wonderful doctors the OBGYNs and urologists that helped um inform me in anticipation of this episode what is good for the woman is good for the egg and for fertility and for pregnancy and what's good for the man is good for the quality and production of sperm and for fertility and pregnancy put differently whether or not we are male or female the things that we can do to optimize our fertility are the exact same thing things that we should all be doing to optimize our vitality and our longevity and I realized today's episode was so much the Deep dive and um fairly broad as well that it ended up being fairly long and extensive and yet we still have not touched on any of the important themes that I know a number of people want to know about so for instance menopause andropause PCOS and other themes related to hormones and reproductive function in biology and I promise that we will have episodes both solo episodes and episodes with expert guests in the future to cover all of those topics in detail meanwhile the information discussed in today's episode should serve as a basic foundation for those discussions going forward and hopefully were of interest to you in their own right if you're learning from Andor enjoying this podcast please subscribe to our YouTube channel that's a terrific zeroc cost way to support us in addition please subscribe to the podcast on Spotify and apple and on both Spotify and apple you can leave us up to a five-star review if you have 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zero cost thank you once again for joining me for today's discussion all about the biology surrounding this incredible thing that we call fertility including the ovulatory cycle spermatogenesis fertilization itself and all the events leading up to pregnancy and last but certainly not least thank you for your interest in science [Music]