Plain English with Derek Thompson - Fertility Needs a Scientific Revolution

Episode Date: July 16, 2025

Couples are having kids much later in their lives. As young people spend more of their 20s and 30s getting established in their careers, and marriage is delayed, and home buying is delayed, the unstoppable force of delay runs up against the immovable object of human anatomy. It is harder for a 40-year-old to get pregnant than for a 20-year-old to do so. The best solution we have for the fertility dilemma of the modern age is in vitro fertilization. IVF is a decades-long practice based on science, so you might think that the procedure is highly predictable, something close to an act of precision engineering. But people who have gone through the process know it can be messy, painful, frustrating, and expensive. So, what would a real scientific revolution in fertility look like? How close are we to a game-changing invention in this space? Today’s guest is Ruxandra Teslo, a scientist and writer. We talk about the fertility dilemma that exists, the fertility technology that doesn’t exist, and how a revolution in egg science could produce a second baby boom. If you have questions, observations, or ideas for future episodes, email us at [e-mail]. Host: Derek Thompson Guest: Ruxandra Teslo Producer: Devon Baroldi Learn more about your ad choices. Visit podcastchoices.com/adchoices

Hey, it's Craig Horlebeck here to tell you that the NFL is back, whether you like it or not, and we are covering all the latest news, trades, rankings, and more on the Ringer Fantasy Football Show with my two co-hosts who are both named Danny. Check the Ringer Fantasy Football Show out on Spotify or on our new YouTube channel. Today, the fertility dilemma and the future of fertility science. In the last few decades, men and women have been having children later in their lives. The reasons tend to be complex and easily simplifies. Yes, it's about labor economics, as today's young people are more likely to go to college

and use their 20-something years to become established in their careers before settling down and having kids. It's about housing economics, too, as the cost of homes is soared in this country, which makes it harder for young couples to feel settled. It's about gender relations, as young people are less likely to date or couple or marry than they used to be. And it's about biology. As young people delay family formation by spending more of their 20s, working or prioritizing personal fulfillment, and as coupling is delayed, and as marriage is delayed, and as home buying is delayed, this unstoppable force of delay runs up against the immovable object of human anatomy. It is just harder for a 40-year-old to get pregnant than a 20-year-old.

The best solution that we have for this dilemma is in vitro fertilization. IVF is a decades-long practice, which is based on science, and so, You might think that the procedure is highly predictable, something close to an act of precision engineering. But it's not. First, the doctors send the woman home with prescriptions for hormone shots. This is for the purpose of stimulating her ovaries. One might like to think that the exact dosage comes from a genetically and biologically precise calculation. But it's more like a rough guesstimate based in the woman's age in medical history.

Second, doctors collect eggs from the old. ovaries. Again, you'd like to think that they have a clear sense of how many eggs they'll retrieve. But here, again, the doctors are often just as surprised as the patient by what they collect. Third, the eggs are combined with sperm provided by a husband, partner, or donor. How many embryos will result from this lab dish fertilization process is, again, kind of anybody's guess. Fourth, the embryos are analyzed for, among other things, chromosonal abnormalities. But what these abnormalities actually mean is yet another mystery. There is, for example, intense debate among doctors and couples about how to think about mosaic embryos,

meaning they contain a mix of genetically normal and abnormal cells. Many clinics and doctors simply don't know exactly what to do with these embryos. Fifth, embryos that are deemed healthy enough are transferred, as they call it, to the woman's uterus. Again, you'd like to think that at this point in the process, success is all but guaranteed. But the truth is, it's still basically a coin flip as to whether the woman gets pregnant. This is the best and most advanced common fertility procedure in the richest country in the world, in an age of scientific wonders. And yet the whole thing is just one long cavalcade of uncertainty, with an overall success rate well below 50% per round. Some couples have to go through

the process several times a year for several years at exorbitant financial. cost, not to mention emotional cost. Fertility is practically the most basic mammalian function there is, and yet the science of fertility feels awfully like a crapshoot at the very moment in our history when we need it the most. I know it might sound a little creepy to some folks to think about the science and technology of fertility, perhaps a little bit matrix adjacent, but the one and only baby boom in the history of the modern world was in part a revolution in science and tech. Many people assume that

the baby boom, that which we associate with, say, the baby boomers, started after World War II, like a spasm of giddy horniness following America's smashing victory. This is simply wrong. The baby boom actually started in the 1930s, and it happened not only in the U.S., but practically everywhere throughout the Western industrialized world. It was somewhat universal among richer countries, and so the only explanations that make sense here must be similarly universal. In fact, starting in the 1920s, 1930s, electric appliances like refrigerators and heating machines proliferated throughout American and European homes, just as advances in antibiotics dramatically reduced maternal mortality, which made giving birth much safer.

Electric machines and medicines probably weren't the only factors behind that first baby boom, but they were critical factors. And if the last baby boom came from science and technology, perhaps the next one will too. Today's guest is Roxandra Tesla, a scientist and a writer. We talk about the fertility dilemma that exists, the fertility technology that doesn't yet exist,

and how a scientific revolution in egg science could produce a second baby boom. I'm Derek Thompson. This is plain English. Roxandra, it's Hesslo. Welcome with the show. Thank you for having me on. We're talking today about fertility, the science of fertility,

and even the future of fertility technology. And I know some folks find any level of attention paid to this topic, a little bit creepy. Like, why should any stranger care about the number of children you have, the number of children I have? Why is this subject important to you? Well, so I think on a very personal level, I suffer from a condition called Policistic Ovary Syndrome, and I'm a biologist. And I think these two things combined led me down a path

of looking a lot at fertility science and realizing that I had been sort of misled by doctors and by sort of, I don't want to sound conspiratorial, but society in general and like sort of common medical knowledge in terms of like what my condition meant. And also, So even with all of the sort of biological training, what I could find and how badly underfunded and under researched the topic of fertility was. And then it just turned into like a broader interest, I guess, because, you know, I am a woman who wants to have a career. I want to have children as well. And there are all these conflicts that as I'm approaching my 30s, I'm 28 now, are sort of like, you know, becoming more apparent to me.

And I'm also seeing women older than me sort of grappling with these kind of things. You touched on something that I think is absolutely critical here, which is this tension between modernity and biology. In rich countries around the world, birth rates have fallen to historically low levels. And a part of that is that many women, especially educated women, have been delaying fertility if they want to work, if they want to build a career in their 20s. You've written that women who make this decision

are looking at the data in a very rational way. Women face a significant penalty in earnings after giving birth. Can you talk a little bit about that earnings penalty? There's a 16% gender wage gap on average. And, you know, in developed countries, a very, very large part of that wage gap is a so-called motherhood wage gap.

So basically the sort of wage gap starts to appear when women start to have children. And this is particularly stark in professions that are like high pressure, high demand professions, like medicine law or, yeah, medicine law, academia, you know, all of these professions that we kind of as a society, for better or worse, hold in high regard. You call them greedy careers?

Gritty careers, yes, greedy careers. That's the term that Claudia Goldine, the winner of the Nobel Prize for Economics in 2023, uses for these careers. So these are careers where the more work you put in, the more hours you put in, the sort of return to your input of hours is exponential. It's not linear. You can always work more and you can always gain more. And probably entrepreneurship is like the perfect example, right?

Like in entrepreneurship, you know, there's never enough that, you know, there's never too much that you can do, right? Like, each, like, extra hour that you take for a meeting with someone, it might lead to the next company, it might lead to the next business partnership and so on. So I would say that's an extreme. But a lot of the other, like, sort of high-stakes careers, like medicine and so on also quite greedy. We could do a whole hour on delayed fertility and why so many people have fewer children today than they had in previous decades.

We have done shows about that. And, you know, to circle some of the conclusions, that I reach from those shows, I don't think this is a simple topic at all. I'm not even sure that we have a simple way to describe how complicated it is. I think it's about economics. I think, you know, the earnings gap that you described is absolutely a factor here. It's about technology. I think contraception allows people to control fertility today in a way that's historically unusual. I think it's about sociology. I think people date less. They get married less frequently than they used to. And you've touched on this as well. It's about trade-offs. I mean, parenthood is sacrifice.

You don't sleep. You can't parent hung over. Trust me. I've tried. You can't work full-time with the baby. Trust me again. I've tried. So I want to push even deeper into this core dilemma here, which is that the economics and the culture and the technology of the modern world are conspiring, you could say, to delay fertility. But this is running up against something else, which is biology. do you think is the most intelligent, sophisticated, scientific way to think about how pregnancy gets harder as women get older? Yeah, so basically, we know that per month chances of conception for women, let's say, in their 40s decreased to 5% from something like 25% in their 20s. And we also know that, you know, a significant proportion of women, you know, the fertility starts to

decline after a woman after 35 and that a proportion of those women will really struggle to conceive naturally. So it's not just like a per month problem. It's like a sort of, you know, even if you try for a year, this is how infertility is defined like medically. If you try for a year naturally and you don't conceive, then you're kind of diagnosed with infertility. And that starts to increase after 35. The main problem here is the aging of the egg. So basically, women have a complex reproductive system. We have a uterus. We have eggs.

We have ovaries where we have the eggs. And a very important point here is that this aging, the aging of the reproductive system of women is driven mostly by the aging of the egg, not the uterus. And you can see this very clearly when you look at data from like the chance of pregnancy using donor, young donor eggs. And when women in their 40s use young donor eggs, their chances of pregnancy are quite high, they're very similar to the chances of pregnancy of women, you know, in their early 30s, late 20s, which clearly shows that's like a very good

control experiment, clearly shows that the reason why, you know, their uterus, the rest of the reproductive system is quite capable of, like, you know, holding a pregnancy and, like, having a pregnancy. But this aging of the egg is, like, really what's driving, you know, the sort of decline in fertility with age. I want to put a pin in that because it's obviously so important if we want to think about the science and technology of fertility in the next few decades. The key here is egg health, right? The key here is understanding the science of eggs. before we get to the science, there's a large group of people, I think, who believe the best way to solve these kind of problems are with policy interventions. And if you look around the world, many governments have responded to declining fertility by introducing this enormous set of policies.

We have more maternity leave and paternity leave. We have preschool programs. We have tax benefits for parents. We have child tax credits here in the U.S., which were just expanded with the new Trump law. I think it's fair to say that if these programs worked, their success has been moderate at best. So why do you think in the big picture it's been so hard for government policy to increase fertility? There's complex answers to that. And I would also say that government policy maybe even more surprisingly has failed to decrease the gender wage gap. So there are a lot of policies that were

targeted specifically at the gender wage gap to help women, you know, navigate the, part of their careers. And especially again in these greedy careers, you can't really compensate for lost time, especially in your 30s. And this is the important part that I would also like to highlight how important 1 30s are for these greedy careers. We have data to show that, you know, the more you delay, the better it is for your career. I'm not saying necessarily that the more is a childbearing. And I almost call it like escape velocity. There is a point in your career where you become established now that you can afford to take some time off and you can afford to sort of I mean, you know, if you take 10 years off, time off, then it's not great.

But, you know, once you become established enough, and I think everyone here knows this, like for example, in academia is becoming a principal investigator and that usually happens in your late 30s and so on. You can, it's not that you can just kind of like take time off, but you have like a more stable situation. But it's very, very hard to take time off or to, you know, not take risks in your. your 30s if you want to have one of these careers. I want to scope out here a bit because you and I both went to college. We're both enmeshed in the culture of what we're calling greedy careers. We agree that the smart way to think about this problem is to create technologies that extend fertility deep into one's 30s and early 40s. But I want to acknowledge here an alternate viewpoint that

says that what needs to change is culture, right? There are some folks who say, no, prioritizing work is the problem. People should just get married earlier. They should have children earlier. We shouldn't try to push against the biological limits of our bodies. What is your response to that? You know, a lot of people are arguing on that point that we should change culture to be much more sort of, you know, that we shouldn't encourage women to the, we shouldn't invent these new technology to encourage women to delay childbirth because we're kind of like creating this like sort of negative feedback loop where they have like less and less children. But my point is that we're already seeing a decrease in, you know, a delay in childbirth.

And like, Gen Z women are having less children than millennial women were having at their age. And unless we develop this day, like, this is no longer a matter of, like, encouraging women to have children later. Women are having children later. And unless we have this, unless we do something, unless we invent this technology that goes beyond policy, unless we do the technology, it's not about encouraging women to have children later. It's about like helping those women who have, who will have mostly chosen already to have children later, actually have the children that they want. I think that's such a critical point, that government policy can work at the edge to make it easier for people to take time off. It can make it a little bit cheaper to have a child by subsidizing certain aspects of childhood.

But government can't change the fact that having children is no longer a norm for young women and men in their 20s. So you and I are trying to execute something that might be a little bit unusual. I think a lot of people, when they look at this issue of fertility, they think about behavioral and policy solutions, right? They don't think first to how do we invent some new fertility technique through science and technology. But one really interesting point that I've heard you make is that there's other social dilemmas where behavioral and policy interventions kind of failed, or at least did very

little, and we needed a breakthrough from science and technology to achieve real progress. Can you name a few of those examples where you see maybe fertility can be like that? Yeah, so one of the very, you know, recent ones is obesity, right? So we have, you know, Western countries have struggled with obesity and sort of associated comorbidities for like decades now, and we have had all sorts of programs that sorts of social programs that, you know, promote healthy eating and so on. But it just turns out that our minds are kind of like, you know, not adapted to resist to the sort of temptations of the kind of food environment of the modern world. And then you have this GOP-1 agonists. So the new therapies

that, you know, people know them by different names like some Ozympic, Samagutai, Monjaro, you know, all of these are kind of names for the same thing. So these new therapies, that now pharma companies are like racing to develop and they're all like, you know, in a fight, there's this fight between Novo Nordisk and Eli Lilly for biotech geeks. You know, these therapies work very well. And I think that's a great, great example because, you know, I know, I actually know personally people have struggled for years with this obesity and I have felt guilt and they have felt, you know, there's all sorts of like mental health issues associated with it as well. And then you have this drug and we're making it better and better because like people were saying at the beginning like,

oh no, you're going to become dependent. It's just going to have so many side effects. And it turns out like my parents, you know, I recommend it to my parents and, you know, they couldn't take the first version of it. But now they're making it better and better and they don't have side effect. Well, I think obesity is such an interesting example because with obesity, I love the way you framed it. There's a mismatch between the architecture of our calorie-seeking brains and the calorie abundance of the modern world. And it turns out that, while behavioral interventions are not often successful at fixing that mismatch, a pharmacological intervention is very good at adjusting our minds or our brain gut balance. And in the same way,

we're talking about here with fertility is a little bit of a mismatch, right, between the contour of the modern career, the shape of modernity, and human biology. And so let's talk a little bit about fertility technology that exists, and about fertility technology that could exist. First, what exists? We'll start with egg freezing and in vitro fertilization, otherwise known as IVF. Can you explain the science here?

Why does egg freezing work at all? Yeah, so the reason why egg freezing works at all goes back to my earlier point about why women's reproductive system ages, which is the egg, right? So the reason why, you know, and I just brought up that women who are in their 40s and they use young donor eggs, they usually can conceive at similar rates to women, like very, very small difference between them and women in their 30s or late 20s. And basically, when you freeze your eggs, you act as your own young egg donor or less. And basically, you know, the process of egg freezing used to be quite inefficient. The first reported birth was in 1998, 1986 from egg freezing, but it was very inefficient.

It was only used for extreme cases, for example, during cancer treatment, but then in the mid-20, so to protect the eggs from, like, you know, all of the sort of damage that you could get from, like, cancer treatments. But, you know, in the mid-20, 2000s, people introduced this new techniques of freezing eggs it's called fast freeze vitrification. And it kind of started to take off. It works very well. I mean, you know, most studies show that if you do it at a clinic that knows how to preserve

your eggs, then that's a big if. And unfortunately, clinics don't publish data on this. But, you know, if you do it well, frozen and thawed eggs kind of have the same type of developmental competence as like, you know, fresh eggs. So IVF has been with us for a while. I think most listeners are familiar with IVF. How well does it work compared to, say, trying naturally? Yeah, so that's a very interesting question.

And it's quite a hard answer question to assess, to answer because usually people who try IVF, try IVF because they have some sort of infertility problem. Also, the rate of failure of like conception and the human body is not really very well assessed because you don't, you know, people just try and like at some point they get pregnant or not. It's hard to say how successfully it is compares to an actual conception. But we do know, like, I can tell you like how well it works for women of different ages. So for women under 35, about 50% of cases of women out of 35 do IVF. So in vitro fertilization just to begin with what it is.

It's literally fertilizing an egg in vitro with the sperm. And usually you do that for various reasons. If you're a woman under 35, in 50% of cases is because of male factor in fertility. And basically that just allows you to like, you know, kind of artificially fertilize the egg with sperm and like sort of bypasses the problem with male factor infertility in many cases. And for women under 35, only 50% of cases are related to female factory infertility. And that can range from stuff like polycystic ovary syndrome, which is a problem with ovulation. So you don't ovulate regularly.

And actually in vitro fertilization, you induce ovulation sort of synthetically. And actually women with PCOS, which is what I have. And I didn't know this. Actually, do have good success rates with IVF. They don't have lower success rates than women with things that don't affect their eggs. so they don't, yeah, they don't have, they have good success rates. And other factors are like tubal factors. Like you can't travel through your fallopian. So the fallopian tube is the thing that connects your sort of ovary to your uterus and like the egg has to travel to it. So some women

simply just have some sort of blockage and the egg can travel through it. And again, that has nothing to do with the head quality itself. It's just about like, you know, it can't travel. Then you have endometriosis, which is a bit more complicated because endometriosis is the information of the uterus and it can actually affect the ovary as well, and that's a bit more complicated. And then you have women over 35 for which increasingly they use IVF because of the fact that their egg quality starts to decrease. Their egg quality and egg quantity starts to decrease. So then they're more like age-related infertility. I will say, you know, the thing about IVF is that it is kind of terrible for a lot of

who go through it. It's expensive. It's certainly more art than science. If you're the woman, you're stabbing yourself with hormone shots that can leave you feeling drained, bloated, or just gross. It's stressful. It's painful. The process of taking the eggs, retrieval, as it's called, is quite intense, requires anesthesia. And then after all that, it often results in no embryos, in no viable embryos. So there is a lot of room for improvement here. What are some ways we could make IVF better. They usually tell you that for embryo transfer success rate. So for example, for women under 35, it's usually somewhere between 40 to 50% chance of life birth for an embryo that you're transferring. But that's if you get any embryo at all. In general, women under 35 do get

embryos from their cycle. But there is a possibility that they won't get any embryos. And the number remember as you get that are morphologically, you know, people assess them morphologically, they are morphologically, you know, good and assessed as like implantable is directly proportioned to the number of eggs that you retrieve. So obviously, if you're younger, it's easier. Then the rate of success of IVF decreases a lot with age after 35. So for example, for women who are between 40 and 42, I think a national average in the U.S. is 13%. per cycle. And if you do PGTA, which is like if you assess whether the embryo is, is, you know, chromosomally normal, then the success per embryo transfer is higher. It's like around,

again, around 40 or 50 percent. But that's because you've already selected an embryo that is genetically normal. And your chances of having an embryo that's genetically normal are low for a woman in between 40 in 42. So actually your chances per, you know, procedure itself, like the egg retrieval procedure per IVF procedure is more like 13%. So you have to be very careful when you look at these tasks, like, whether you look at like, is it per procedure, is it per embryo transfer? Because if you do it per embryo transfer, they can just consider like, you know, the best embryos that we tested. But you, a lot of women might not get any of those embryos, right? There's a larger dilemma that we're circling here, which is that fertility and women's health don't

receive nearly the same levels of funding that major diseases receive. Even though fertility is the basis of life and the trends that we've described make it harder for many couples to conceive. The state of fertility science is surprisingly weak, underdeveloped, right? Advancing quite slowly. IVF is the best we've got in many cases, and it's essentially a process of trial and error rather than precision medicine. Why do you think fertility and maternal health are underfunded fields? Yeah, there are many reasons for this. So one of them is, you know, just kind of like cultural inertia. So I want to say the name of a book, The Emperor of All Malities. And what disease do you think it is about?

I happen to know that. Yeah, Siddhartha Mukherjee's book, The Emperor of All Malities, is a book about the history of cancer. Yeah, exactly. And I think that this kind of shows how cancer is seen in the public consciousness, right? Like, it's seen as this like, the Emperor of All maladies. And we had a war on cancer. And I don't think it's coincidental. We have so much funding on cancer because it's seen as this, I mean, it is a very horrible disease. It's not just seen as a horrible disease. But my point is that we tend to treat and we tend to fund things that are like lethal, that like sort of cause death.

We have in general much less, we don't see things that, in general, that affect life quality is as important. So I think that we just don't, you know, we haven't really invested a lot in women's health and sort of we haven't seen fertility as something, like extending fertility as in the same way that we see finding disease. So that's one part of it. I think another part of it is just, you know, I've been digging deeper into like the sort of needy greedy of this.

It's just like the policy, how hard it is to study it from like a very sort of like practical perspective. So, for example, getting, you know, getting access to human eggs and being able to fertilize those eggs just to study, no, in order to implant them. It's just very, very, very hard to get approval for that. Very few labs can do it. And, you know, I sometimes talk to researchers and I ask them, you know, they have very exciting research that could maybe, you know, improve, we could learn how to improve egg quality. And I'm like, why haven't you, why have you just tried this in mice, right? like you have to consider that they're first of all resource constrained because they don't get a lot of funding as I just explained.

But then they tried this thing in mice and I'm like, why didn't try any humans? And they're like, oh, we just don't like I don't want to waste human eggs because they're so hard to get. And if you want to like study embryogenesis and like sort of the process which the embryo forms is even harder. And so few labs can get access to that. And there's so much legislation, you know. You know, we can, I mean, people of different sort of cultural and political backgrounds will disagree on this. But, you know, the fact that we treated with so, with so much, you know, in my opinion, overcare makes it very hard to make progress because you kind of have to understand the process of fertilization, the process of, you know, how egg develops and so on and then how the embryo develops in order to be able to make IVF better. because, you know, how are you going to make idea better unless you understand how the embryo forms

and you understand the biological basis of that? And we don't really understand it. I'd like to depart now from the world that exists and enter the world that might exist if fertility science technology advanced tremendously in our lifetimes. Paint the picture here. What does the frontier of fertility technology look like to you? What should we hope to invent?

Yeah, so I think that, we can do at the moment a lot to make the IVF process itself better. So we know that even for women who have healthy eggs, it doesn't work very well. We can make the stimulation easier. We can, you know, get those embryos to develop at a much higher rate. We don't need like 50% success rates. We can we can take that higher. We don't need young women to go through multiple cycles as they sometimes do. So that's one thing that we can do. But then on like the very sort of more like long-term horizon, sort of sci-fi level, I think we can create actual new eggs from other cells of the body and have an abundance of eggs, and then you don't need to worry about anything.

All right, and this is the sci-fi part that I really wanted to talk to you about, and it involves a frontier of science called induced pluripotent stem cells. I would like you to bring this all the way down to Science 101. what are induced pluripotent stem cells and how could this science dramatically improve fertility rates? Yeah, so induced pluripotent stem cells, just to begin with a bit with the science, so, you know, you have an eye cell and a skin cell, and they all share the same DNA. The difference between them, and they're all, like, you know, descended from the same,

you know, embryonic stem cells. And the difference between them is mostly epigenetic. So they're epigenetically programmed to be an eye cell or a skin cell or whatever. And it turns out that if you induce these things called Yamanaka factors, these four transcription, they're called transcription factors into like fully differentiated cells from a human, you can turn back the clock and you can make them back into something that is more like a stem cell. And that's why they're called induced propotent stem cells.

They won, you know, the inventors of this won the Nobel Prize in 20. 2012 for medicine. So these induced puripotent stem cells, then act the stem cells, and then they can be turned back into other cell types. And this is actually widely used in medicine now, you know, in cancer therapy, in drug testing and so on. Like, it's almost like, you know, in Harry Potter, you have transfiguration. Here you kind of transfigure one type of cell to another through the intermediate of the body of step. Let me slow this down because it truly is the most extraordinary thing if this science moves forward. Several years ago, I went to a conference on the frontier of medicine, and one of the presenters was working on this field of pluripotent stem cells. I had never heard

of this, by the way. And he says, essentially, imagine a world where we could take a scrape from your arm. So we take forearm skin cells. And we could use this science that you described, Yamanaka factors, to turn those skin cells back into stem cells, to almost pull the cells. To almost pull the cells back into their stem cell state. And from here, we could develop those stem cells to become other differentiated cells. After all, they are called pluripotent, plurie, like plural, meaning many, because these are cells that can become any number of things. We could grow them into, let's say, a liver if what the patient needs is a liver transplant. And now this already sounds quite sci-fi. The idea that if I need a liver transplant, that's a genetic match,

I might be able to grow my own liver from induced pluripotent stem cells derived from cells just scrape from my arm. That's completely wild. But what we're imagining here is actually wilder. In the distant future, we wouldn't just grow pluripotent stem cells into an organ, like a liver, we would grow them into an egg. And this would mean that older women could essentially develop youthful, healthy eggs from their own ordinary epidermal cells. Can you pull us back to reality here and ground us in where does this science exist now? Yeah, so I think, well, there is already, you know, a company called Gamito who,

actually is turning induced pre-prudent stem cells into ovarian support cells. It turns out that's much easier than making them into eggs because you're just kind of like creating an artificial ovary. It's very hard to assess how far away we are from creating eggs from induced prepotent stem cells. And the reasons are that most of this research is now happening in private companies and it's a bit hard to assess, you know, what they're doing. I think it is very hard because the egg has to go through these like very specific processes called it's a person called myiosis. It doesn't do the normal cell division that most cells in the body do mitosis. It's it has to contain all of the proteins that a lot of the proteins that the future embryo will need in order

to like survive. It has to go through this epigenetic reprogramming processes, just like a very complicated cell type. So I would say that this is a very, very complex scientific question. I think we will get there. I think the question is like, how will we test it? How will we make sure it's safe? How will we compare it? And I think that it would be very useful if we had sort of public funding for this. And the reason for that is that I think it will be. rely on a lot of technologies that are not quite there yet. And so just to get a really clear understanding of how it would work, because we'll end back in reality. I just want to play out the sci-fi situation just one click longer, is the idea

that there's a 40-year-old woman who wants to get pregnant, she goes into a fertility clinic, and then in a world with what you call IVG, in vitro gametogenesis, what happens next? Can you just tell the story of how this technology would work if, let's say, the year is 2040, it's a reality. Yeah, so she would just get one of her, this cell in her body that is in an egg, and people are debating which cell is the best cell to start with. In a lab, someone would turn into and use peripotin stem cell. It would share the same DNA with a woman. And then they would turn into an egg.

And then they would do the normal IVF process that people do. regularly. I think that's kind of how people envision it. But there are other avenues. People are also trying to do repair of eggs that are aged. So to sort of try to like, you know, repair the DNA damage that has occurred. So that's another sort of maybe more midterm solution to like aged eggs until we get to IVG. But yeah, that would be like. So there's. So there. There are other things besides IVG that we can do in the meantime as well. And I think we should research it much more. Absolutely.

So is it fair to say by summary that you see a sort of short-term, medium-term, long-term technological solution to the fertility dilemma? In the short-term, we need better science, better experiments to improve the IVF process that actually exists. In the medium term, we want to use the science of induced pluripo-pore. in stem cells to assist in the IVF process to essentially, you know, to repair ovaries or repair eggs, rescue immature eggs that would have been maybe discarded in standard IVF. Yeah, yeah, with the startup called Gameta, yeah, yeah.

Right, that's the startup commita. And then in the long term, there's this sci-fi idea of the 40-year-old investment banker who walks into the fertility clinic and someone, like scrapes her thigh and turns the skin cell into an egg that she can implant after it's been fertilized by her partner, right? So is that the landscape here of short-term, medium-term, long-term as you see it? In the long, in the medium to long term, you can include other scientific solutions. So for example, as I said, like probably reversing DNA damage of the, which is DNA damage of the egg is the main source of why women can't have children. That's another thing that

people are pursuing, for example. So that's another avenue, but it's also like medium to long term, but again, that's how I would see it, yeah. Big picture here, it does seem like these sort of advances require sustained scientific investment. Yes. What needs to change in the institutions of science and the field of science to support this kind of long-term investment in revolutionizing fertility. So I think that, you know, just, you know, at a very basic level, making it easier for researchers to get eggs or, you know, just kind of these policy changes would be helpful. But in terms of like the funding landscape, funding fertility research per se would be very helpful. A lot of the people who research fertility and a lot of the people who, they come from, you know, developmental biology.

And they just stumbled upon fertility because it's kind of related. Right. You're studying development is related to fertility. But like the people who discovered induced prepotone stem cells, they were a redevelopment of biologists. Very few people, you know, start out as fertility science. Like, they start out like, oh, I want to study fertility. No, they started DNA damage or something else. And there isn't even like an institute as far as, I mean, I think there's one in the U.S. now. But it's not like a proper field in the same way that cancer, like cancer has like dedicated things. There is, there are conferences for like reproductive science, but they're very like applied, you know, the basics of like how eggs age, like the all sorts of like IVG stuff

doesn't really get funded by the state. And I think, you know, it doesn't have to be the state. It can be like philanthropic money. I think a lot of people, you know, are very interested in all sorts of like futuristic like sort of reproductive technologies, but somehow when it comes to the woman, they don't really think about how to do that. And I think there's a lot of opportunity here for philanthropic funding. I think there should be much more of it. It's such a neglected area that if you want to have impact, you can probably have so much impact. If you're someone with money, you can probably have so much impact so easily because it's not like cancer. Again, where like there's already so much investment that like every marginal, you know, dollar is like

not going to do that much. But like here, if you just invest a bit, I think you could have a really big impact. So if you have money and want to fund fertility research, you should. Well, I think it's interesting because if what some folks you'd be interested in is what it would take to have another baby boom, if you look back at the first baby boom, right, what happened in the 40s and 50s, that was a technological revolution in part. Parenting got easier and cheaper because of the proliferation of household technologies, washing machine penetration, quadrupled, vacuums, refrigerators, stoves, electric power, all of that grew during this period. It made it easier to raise children. At the same time, early anti-microbial medicines made giving birth much safer. And so in many ways, the first baby boom was assisted by a revolution in science and technology. And it's interesting because right now, I think when a lot of people think about, you know, how do we raise fertility, they think about policies, they think about money, they think about tax cuts, and they think about free services.

All of that's fine. but I'm really happy that you came on the show to talk about reintroducing science and technology to this discussion because science and technology might have been critical to the first baby boom and they might be critical for another baby boom. Yes, yeah. And I think people, I think there's a bit of a almost like a political mismatch here. A lot of the people who want to help women don't want to think about fertility. And a lot of the people who think about fertility think that it's bad. to invest in fertility because women will be more or will delay more. And I just kind of want to say that, like, you know, you can be interested in fertility

and also care about women. They're very convergent things. And also, if you want a baby boom from the fertility perspective, you shouldn't be worried that you're further encouraging women to delay childbearing because they already are doing it. And this is about saving, like, this is literally about like allowing these women that are or delaying childbearing to have children. To have it all. Right.

This is about letting women have it all in a way. From whatever perspective, you're coming. Please be interested in fertility because I think both sort of like all cultural stripes, I think should be interested in that. And I think it's a mistake to think that it's at odds with their goals. Roxandra Teslo, thank you very, very much. Thank you so much for having me on.