What we now know about eggs, sperm, and fertility (new data, new ideas)

0:00This show is sponsored by Primidine, a clean, natural and science-based spermidine supplement that's been a long-time staple in my own longevity stack. Because studies suggest that through autophagy, spermidine increases healthspan and upregulates a range of health markers, from memory and cognitive function to heart health, hormone balance, fertility, and even hair growth. Plus, you can be assured that all ingredients undergo rigorous third-party testing. Buy Primadine now at OxfordHealthSpam.com and use the discount code DrSophie, that's D-R-Sophie for 20 % off. This show is sponsored by Microbes, an award-winning liquid probiotic that's now a staple for me because Microbes, with a Z on the end, is different.

0:47For one thing, they source directly from the soil on their Wiltshire farm, meaning more diversity with at least 15 strains of good bacteria in every single shot. It's brewed so it can survive in the stomach and a remarkable 92 % of customers say it makes a difference. Plus they offer micro-friendly cleaning, gardening and even microbes for dogs. Buy now at microbes.co.uk and use the discount code sophie20 for 20 % off. Hi I'm Sophie and this is Age Well with Dr Sophie Schotter, a space devoted to all things health, wellness and longevity. Because for me, aging well is about looking and feeling like the best possible version of ourselves inside as well as out.

1:31So together with my producer Fee, I'll be deep diving into the latest research, sifting fact from fiction. I'll also be talking to all kinds of trusted experts tapping into their knowledge, along with bringing you conversations from a range of interesting women and men finding out how they age well. So this is my show. Welcome along. And as always, thank you so much for listening.

2:00Dr Sophie Shotter:So Sophie, this is another pretty hefty topic and we're going straight in as always. I know we're going to focus on egg and sperm quality, but should we start by giving, I guess a quick overview of the various potential reasons that people might struggle to conceive. Yes and I'm so glad you haven't used the word infertility because I really do think there's so much negative language around this subject and people can feel really quite marginalised or ashamed by this word, both women and men in different ways. The first thing to say is that recent research has shown that fertility rates in England and Wales have fallen to their lowest levels since records began.

2:42So a lot of people are talking about this fertility crisis and one in five of us either have or will struggle with fertility. And a lot of experts point to these endocrine disruptors and microplastics, which we'll get into. But traditionally, one of the most common causes of difficulties in conceiving is age. For most women, the ability to conceive decreases fairly rapidly after their early 30s due to a decline in egg quality and also egg number. but you can say it only takes one egg if it's good quality. Other reasons might be things like PCOS or issues caused by sexually transmitted infections or fibroids or endometrial polyps as well.

3:22Or of course, there may also be issues with a man's sperm quality. This might be impaired sperm production or development. It could be impaired sperm motility. So that means how well it moves or swims. low sperm count, possibly genetics, infections, or again STIs. And these challenges to conceive might not be one thing. It might be a combination of any of these things. And sometimes, frustratingly, we just don't know. Anecdotally, there's a lot to be said for trauma and stress. And I know a lot of people who almost like the moment they stop trying to conceive and the pressure that comes with that and they start focusing on other things in their life, lo and behold, the conception happens because actually trying to conceive in its own right can be a very stressful process.

4:09But there's an awful lot that people can do to improve their fertility.

4:14Dr Sophie Shotter:Yeah, and you know, it's really funny you mentioned this about stress. I know of two people who were struggling to conceive and as soon as they stopped trying, they got pregnant. So yeah, I do really wonder if the stress hormones have an impact there. So again, we're honing in on the egg and the sperm. Where shall we start? I'm going to break this down into three core areas, diet and nutrition, lifestyle and then supplements. I'm also going to add that I'm not a fertility expert. I'm a doctor with a natural interest in all things health and wellness and I'd advise anyone that's struggling with fertility to see a qualified specialist.

4:48I'll also add that everything I'm about to say is based on the latest data and research because clearly there's a lot of marketing out there designed to hook in some very vulnerable people. So diet first and we know that eating a diet high in polyunsaturated fatty acids is important either from low mercury fish or from a fish oil supplement. There are lots of studies to support this and again I'll pop these in the show notes as I always do. Ideally both men and women should eat a moderate amount of low mercury fish and possibly even supplement with a good fish oil that contains both EPA and DHA.

5:24Vegans and vegetarians can also get ALA which is alpha linoleic acid and the body converts this into EPA and DHA. You can get that from flax, soybeans, chia seeds, walnuts or again a good quality supplement. Don't shoot the messenger but women who eat a lot of trans fatty acids have been found to have a greater risk of fertility challenges and this is a type of fat found in lots of fatty fried foods. Just a quick note on walnuts actually and though it seems random a doctor called Howard Kim and his colleague Wendy Robbins are currently researching whether walnuts improve sperm quality with some quite interesting and very positive results so watch this space.

6:06The research on meat has been mixed so I'm not going to get into that until I can see more robust data. Caffeine is an interesting one. It's widely accepted that coffee during pregnancy should be limited because it's a potential stressor to the baby, but we don't know whether it impacts conception. So a 2017 meta-analysis found evidence that caffeine intake might be associated with miscarriage, but the research didn't find any association between caffeine and fertility itself. So again, let's watch this space, but reducing caffeine intake might be helpful. There are question marks around soy, which contains very weak estrogen-like compounds called phytoestrogens but these phytoestrogens have not been shown to negatively impact reproduction in trials.

6:51Some small studies have even suggested that soy might be beneficial to women undergoing fertility treatment but again we need more data as always. As always. I think it goes yeah and you know it's so difficult for this data to be produced because it's expensive to do.

7:07Dr Sophie Shotter:Yeah. I think it goes without saying to highly avoid alcohol and highly processed foods. Alcohol has been shown to damage sperm motility and morphology. So again, motility is how well the sperm swims or moves and morphology is the shape of the sperm and this shape impacts the sperm's ability to penetrate the egg wall. Likewise, excess alcohol in men can result in disrupted sex hormones, which can again have an effect on fertility. For the women, a recent Danish study found that drinking one to six alcoholic drinks per night may be linked with higher rates of fertility challenges in women over 30.

7:42Dr Sophie Shotter:Okay, so that's nutrition. What about undiet? What about lifestyle? It's a lot of the things that we try and do regardless of trying to conceive. So exercise is one important aspect, but it may be different for the sexes. In one study in men, six months of resistance training was shown to reduce inflammation and oxidative stress in semen. But for women, While exercise is definitely a positive, really intensive exercise can raise cortisol. And we know that cortisol, our stress hormone, can impact a woman's ability to conceive. Other studies show that stress is one of the things that degrades sperm quality.

8:18Dr Sophie Shotter:This is interesting. And this kind of chimes with what Claire from Women's Health was saying about cortisol and intensive exercise for women. And a little bit about what C. Sims was saying as well. So that all tallies. so this is apart from that this is basically all the same advice for men and for women broadly speaking yes it's the mediterranean diet though if you troll the internet you'll find nuance around a sperm health diet for example again lots of walnuts and also dark chocolate but apart from this interesting albeit very small study on walnuts the evidence is lacking and again i don't think people should get hung up saying that dark chocolate is having a moment following the herbalist Simon Mills talking about its virtues on another big podcast.

9:01So it can potentially help. Other foods linked to good sperm quality are spinach, eggs, bananas, pumpkin seeds and garlic. Garlic, for example, contains something called allicin, which improves blood flow. I've read that pomegranate juice has been linked to an increase in sperm count and quality. But again, let's keep it simple. Focus on a fresh, fibre-rich, plant-forward diet with good quality fish.

9:25Dr Sophie Shotter:it seems there's an increasing focus on food as medicine exactly and broadly speaking i am an advocate for this there's also a little bit of nuance within this so some experts talk about women eating leafy green vegetables because these contain chlorophyll which is said to support the uterine lining or she should eat mineral rich foods to calm her nervous system and we could easily link here to our episode with caroline allen and her terrific approach to micro and plant-based minerals. Yes and Paul and I have noticed a big difference since taking her beam supplement actually. Yeah me too and back on to this idea of food as medicine I read an interesting article in Glamour magazine where Lindsay Becker, a fertility chef, talks about the fertility boosting properties of various foods but rather than laboriously read out the list we'll signpost it again in the show notes.

10:15Dr Sophie Shotter:Okay so let's talk about one of our absolute favourite areas of discussion, I love this supplements. Yeah and the big one is folic acid or vitamin B9 but if you remember our at-home health testing episode from last year I'd say it might be wise to stick to methylfolate and we'll link into that episode so people can hear why and what the difference is. More recent studies have suggested that B9 not only reduces the risk of miscarriage but confers other benefits such as better fertility and essentially getting pregnant faster. but if you follow a diet with lots of leafy green vegetables chances are you're getting lots of benign naturally and folate or folic acid isn't just for women because higher folate levels in semen have also been associated with improved sperm count and quality and again dietary folate can be found in dark green leafy vegetables such as kale and spinach and broccoli brussels sprouts but also beans lentils and citrus fruits you might also want to take a really good fish oil supplement because of the reasons I previously said.

11:16Omega-3 essential fatty acids have been shown to help with egg quality, but can also significantly improve the motility or movement of sperm. But I'd caveat this by saying that so much fish is now unfortunately contaminated with toxins. So a good quality supplement might be better than eating fish unless you know the fish is free of mercury and other toxins. Vitamin D is another good one that some fertility experts recommend, but ensure it's D3 with K2.

11:41Dr Sophie Shotter:And they've also heard that maca is a good one. Yes, potentially. Peruvian maca is said to boost sperm count, but the data is limited. Perhaps men can add it to a smoothie as it does have a slightly bitter taste. For women, there's also something called vitex, which is sometimes also known as chasteberry, which is the fruit of the chaste tree. And this is sometimes used for PMS and PCOS. It's also sometimes included as an ingredient in various fertility supplements marketed to women. For example, a nutritional supplement called Fertility Blend contains this Vitex along with other things. And in a couple of small studies, there did appear to be positive findings.

12:21But it's unclear whether these benefits were due to the Vitex or the other ingredients in the supplement. Plus, the manufacturer was involved in both studies, which isn't ideal. There's also something called lactolycopene, which is a newly patented combination of lycopene and whey protein designed to increase bioavailability of lycopene. In a study, it seemed to improve sperm, motility and morphology in healthy men. But again, these are all still small studies.

12:46Dr Sophie Shotter:Can we talk more generally about the lifespan and a sort of day in the month of a woman's eggs? Yes, although we need to be thinking more along the lines of a day in three months as we're talking an average 90-day cycle. So here's the top line explainer. Women are born with their lifetime of eggs and these are stored in the ovaries until they're ready to mature and be released. Either to be shed as part of menstruation, so when we have our periods, if we have periods, or to be fertilised if we get pregnant. What's also interesting is that studies in epigenetics, so how behaviours and environment can affect the way that our genes work, have shown that the future health of a child can be influenced by the diet and lifestyle of their parents and even their grandparents.

13:28so when we consider that girls are born with all of the eggs they will ever have this means that when our grandmother was pregnant with our mother our mother's eggs were developing in our grandmother's womb including the tiny egg that would eventually go on to create you and i and that's quite amazing when you think about it yeah so while male sperm regenerates every three months or so women are born with a finite number of eggs roughly one to two million when we're born which dwindles down to about 400 ,000 when we hit puberty. And the thing is while you can't change the number of eggs you're born with you can change the quality.

14:02Before I go on though one super interesting thing to say is that we now know a woman's egg dictates which sperm is allowed in which I think is really funny. And these eggs are very picky. So a woman's egg is basically more receptive to sperm with things like good shape and motility. So it's always used to be oh the sperm goes swimming and hunting for the egg and the winning sperm when actually it's the egg that chooses which sperm wins yes so this new study has found that a woman's egg released chemicals which leave a sort of invisible trail of breadcrumbs that the sperm used to find a woman's unfertilized eggs but these breadcrumbs act differently on different sperm from different men basically a woman's egg chooses which sperm is successful and a woman's egg doesn't always agree with her choice of partner because females choose males who are more genetically compatible.

14:52It's fascinating. So again, to look at the cycle of an egg, it takes around 90 days for an egg to mature and be ready for fertilisation. And this is a window of opportunity for women to get their eggs in optimal health. And the key areas of focus that experts talk about are good blood flow and oxygenation, hormones, nutrition, and stress reduction. Can you break this down a little bit? Sure. So blood flow and oxygenation is about good circulation to the ovaries because it will help to nourish the eggs. So this is really simple things like exercise, drinking enough water to prevent the blood from being too thick from dehydration.

15:26Nutrition and stress I think we've covered quite well. Hormones is a little trickier because this can be affected by stress, environmental factors and by diet. So for one thing we've previously talked at length on the podcast about endocrine disruptors. So all of the chemicals and microplastics out there that we know impact our hormones and sperm and egg quality. Yeah and this is so huge from what I've been reading. Yeah it is huge and it isn't some theory it's established fact now. There are actually thought to be around 800 of these endocrine disruptors out there and they're in everything from food container plastics to personal care products.

16:03I'm going to flag two more of our episodes which is the recent one on household chemicals in last year's episode on drinking water. I'm also going to put a little helpful resource in the show notes. Basically we need to avoid as many of these plastics, cleaning chemicals and pesticides as we can. One study has shown that men who breathe polluted air drink polluted water or work with certain chemicals, so from pesticides to plant thinners, are almost certainly damaging their sperm. Plus new research has revealed a rise in chemicals in our rivers are basically feminising male fish. So this study, led by the University of Exeter, found that one in five male fish are exhibiting female characteristics and even producing eggs.

16:44And that's because over 200 oestrogen-like chemicals have been identified in our waterways with traces of contraceptive pills, microplastics and antidepressants, all believed to be responsible for this new breed of effectively transgender fish. I was reading some comments from the journalist Anna Sussman, who points out that women in coastal Bangladesh are reporting higher rates of miscarriage which again has been linked to the quality of drinking water. Anna also points to the fact that unlike women and men who legitimately choose childlessness in some of the world's most vulnerable populations childlessness is choosing them and I think there's a strong argument that men need to take their fertility as seriously as women do because generally speaking it seems that the conversation here is widely taking place by women and for women.

17:31Dr Sophie Shotter:Yeah, agreed. So we've kind of covered eggs. What about the lifespan of sperm, which you've touched on, but can we hear a little bit more because I don't know so much about sperm? So most men produce sperm all day, every day, but it takes about two months for sperm to fully mature. And people tend to use sperm and semen interchangeably, but sperm is just a small component of semen, which is also made up of various proteins, vitamin C, zinc, and other things. People may already know this, but only about half of all sperm ejaculated actually makes it to the finish line. The rest just swims around in circles, probably refusing to ask for directions.

18:09Another interesting fact is that according to a study in the Fertility and Sterility Journal, regular ejaculation does seem to optimise sperm ability. I'm particularly interested in the results of the largest ever review of studies in sperm counts, analysing nearly 200 previous studies of nearly 43 ,000 men from 1973 to 2011. And it found that overall sperm counts have declined by 59%, which is a huge number. And the average sperm concentration has fallen from around 99 million sperm per milliliter to 47 million, so nearly half. and anything below 15 million is regarded as an impediment to reproduction.

18:51So this trend line is slightly concerning and again people are looking at microplastics and hormone disruptors. Some people also point to boys and men keeping their phones in their pockets near their genitals though we don't have strong enough data to prove this yet. There are also some really interesting startups like Legacy in the US which offers at-home sperm testing and freezing and I think it's fair to say that fertility tech and investment is now very much a thing. At the same time, I think it's fair to say that sperm is something we don't talk about enough. And in the words of the fertility author Leslie Schrock, nothing's going to change in women's health until men take fertility more seriously.

19:28Dr Sophie Shotter:And momentarily off topic, but have you heard about the pro-natalist movement? Yes, and these pro-natalist power couples like Malcolm and Simone Collins, they currently have three kids but are aiming for 13 in a bid to help reverse the birth rate decline. When you consider movements like One Billion Americans and how some governments are spending heavily on programmes to incentivise pregnancy, it feels slightly handmaid's tail-ish and probably a whole other podcast fee. Yeah. OK, let's do some quickfire questions. What about these various ideas that men should only wear boxes and have lukewarm showers if they're trying to conceive?

20:04Dr Sophie Shotter:Is that fact or fiction? Heat does reduce sperm count and overall semen quality, yes, because sperm production is temperature dependent. So exposure to hot tub saunas, prolonged hot showers, tight clothing or even working on a laptop for extended periods can raise growth or temperatures. Okay. And can cannabis affect sperm quality? In short, yes. But as always, more research is needed. I'll pop some links to this in the show notes. Okay. Do raw eggs help sperm quality? I've heard about this trend, but there's no scientific evidence to suggest that eating raw eggs provide significant health benefits or sperm health.

20:43Plus, it comes with the risk of food poisoning, so I would not recommend. Fertility MOTs, useful or waste of money? They're useful in that they can tell you the number of eggs you have left and how you might respond to fertility treatment, but they can't tell you how long it might take to get pregnant naturally. There's a blood test called an AMH test, anti-malarian hormone, and you can buy these kits online and they can be done with a simple finger prick blood sample that you can post off to a lab for analysis. Usually the results are back within a few days. So the test can't tell you the exact numbers of eggs you have, but it's a reliable indicator of your ovarian reserve.

21:18So the number of growing follicles, each containing an immature egg. But again, I will go back to saying that it does only take one egg to fall pregnant. So even people who have low AMHs can fall pregnant, although it might be more difficult. Yeah, good point.

21:36Dr Sophie Shotter:What about lab-grown sperm and eggs? I heard about this. Surely this isn't a thing. Not yet, but it might be in the future. So this is about artificially creating eggs and sperm in a laboratory, which technically means you could have a baby with yourself or even with more than one person in a multiplex parenting arrangement. Again, it all sounds very dystopian, but it's apparently under consideration by the UK's fertility watchdog, which has concluded that the technology could be on the brink of viability. Yes, it could mean that same-sex couples could have biological children together, but it also poses a huge moral debate that I don't think we'll get into right now.

22:16No, let's not.

22:17Dr Sophie Shotter:What about other fertility futuristic stuff that's coming down the pipeline? It seems like there's lots going on in this space now. Yeah, all sorts. I was researching a few things in preparation for the episode. So researchers at Princeton have studied proteins called capepsin B proteases that might decrease a women's fertility so they're looking at blocker drugs. Researchers at Imperial in London are studying how the ejaculatory process can impact sperm. The National University of Cordoba over in Argentina is working on a sperm selection project that helps to identify the best quality sperm and then there's also an amazing researcher called Daisy Robinson in America who has set up a company working on a recombinant version of anti-malarian hormone, which could potentially support fertility and delay menopause as well.

23:07So I think her work is also really pioneering. Modern medicine really is moving on in all kinds of ways.

23:13Dr Sophie Shotter:And keeping it traditional, does acupuncture work? A lot of people swear by it. And certainly here in London, there's a lot of good things being said about Ross J. Barr. I think it's also worth considering seeing someone like Boniface, who we interviewed last summer and I know he has also had success in this field. Yeah I've heard great things about Ross and about Boniface of course. Does orgasm make a difference when trying to conceive? This is an interesting one. Obviously the male orgasm is necessary to release the sperm although remember a small amount can be released pre-ejaculation. The female orgasm has always been thought to be unnecessary for pregnancy but some fertility experts believe we've overlooked something here and that the vaginal contractions from an orgasm helped the sperm to be carried further up, increasing the chances of fertilisation.