In this episode of Trigonometry, we're joined by the director of the new documentary 'Birth Gap' about the fertility crisis around the world, Dr. Shihoko Matsumoto. We talk about her research, her documentary, and her new book.
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00:02:07.060Well, obviously, we talked with you, I think it was last year, about your documentary Birth Gap, talking about the fertility crisis across the world now.
00:02:15.300Not just the Western world, but across the Western world, which is basically the fact we're not having enough children to replace the population as we have now.
00:02:23.040We talked about many of the challenges that poses.
00:02:26.960I think the stat that really stood out for a lot of people from that interview is in Japan where you live, more adult nappies are sold than baby nappies.
00:02:37.780So there's more nappies for people who are in the final stages of life than for babies.
00:02:42.120And this is a thing that is increasingly being replicated around the world.
00:02:47.180And you now have some new data and you've done a lot more research into this.
00:02:51.380So talk to us about where the world is in respect to all of that.
00:03:34.760So the transition of awareness is the one big change I notice.
00:03:40.420And that's a good thing because one of the reasons for making the documentary was to make people aware of what's actually happening.
00:03:46.920But you're right, over the past two years, I've been doing more research because I still wasn't convinced that we really understand this crisis.
00:03:55.220My first paper, now peer-reviewed, I can say that.
00:04:03.580I tend to make documentaries first and then do the peer review after, which is probably the wrong way around to some people.
00:04:08.640But I think this is so important that people need to be aware of certain things.
00:04:12.680And the peer-reviewed research really shows that mothers in Japan and the UK are having around the same number of children as 1970 mothers.
00:04:23.060Let's just park the category of women because there's no such thing as an average woman.
00:05:02.320I'm always talking about women and mothers.
00:05:03.860I really want to talk about men more, and I hope to do that here.
00:05:07.020But looking at the data for women, if you become a mother, 1970s Japan, 2025 Japan, you're going on to have around the same number of children.
00:06:36.840And I decided to do only one thing, which was, OK, let's just prep the data for the next paper, which is going to be about the probability of being a parent by age.
00:07:58.160Well, just to understand clearly, what you're saying is if you look at societies and you measure the average age at which people become parents,
00:08:07.920that will tell you what the fertility rate of that society is going to be.
00:08:11.460You can derive it in two or three rather simple steps.
00:08:14.380OK, but I'm a little bit confused about you say that why that's a single explanation, because there will be causes of that average age increasing over time.
00:08:28.140A number of them, I imagine, not just a singular one, right?
00:08:31.380So some of them will be economic, some will be cultural, social, I imagine, right?
00:08:35.580So I try and think of analogies, and some of them are good and some are not.
00:09:38.840So we're moving downstream of when people would have had children before.
00:09:43.620So the triggers need to be separated from, you know, resolving the triggers now would be like taking the bears away when they're no longer the problem.
00:09:53.680Well, that's a very specifically framed metaphor.
00:09:55.580Forgive me for interrogating it as much as I am.
00:09:57.540But it implies the way this works is you can't move back.
00:10:04.580Some people might say, I'm just thinking it through with you, Stephen, not trying to argue with you at all, that if you remove the conditions that cause people to delay parenthood.
00:10:16.000Well, the reason I'm asking you is, for example, right, my wife and I had our first son at 39.
00:10:20.780I know for a fact we probably would have had them earlier if our material conditions had been different, if we'd bought our flat earlier, if I was making more money earlier, if et cetera.
00:10:36.700So if I go back to that time when I was 35 and I had the income that I had now or the physical, you know, security of owning a property or whatever it might be, we may well have had a child earlier.
00:10:51.460So if you remove that economic constraint from Constantine at age 35, we may well have had kids then.
00:10:59.120And to go back to that evening in Kyoto, once I called up this chart, I was up to three in the morning in disbelief for the reason that this curve, which I'll explain, is symmetrical without bumps.
00:11:14.220So what I mean, if you look at the age of parenthood, motherhood and fathers, we now have some father data.
00:11:19.460My full expectation up to that evening was you'd see a delay in parenthood, some people having children, young, of course, and then maybe mid-20s, you would kind of have a slope going up.
00:11:32.820And then maybe around 30, there might be another uptick.
00:11:37.760Some of you would start to go down, but there'd be another little uptick, mid-30s.
00:11:41.100And then IVF, you would definitely see all the progress in terms of technologies.
00:11:44.980And you'd also say, well, if you go back to 1970, it would be different, but it would be smoother then because maybe there was closer to an average parent back then.
00:11:55.860Most people were marrying at the same time, having kids at the same time.
00:11:59.400So I even doubt myself that this would be a curve that starts smooth and then shows all this bumpiness as people, through autonomy, decide whether to have a child at 35 or 39.
00:13:28.500And if people were to say in the U.S., why are so few Asian-Americans and African-Americans, black Americans, you know, having kids?
00:13:37.040Well, you can see in the data, Asian-Americans are having kids five to ten years later than African-Americans.
00:13:45.020So this curve, to try to explain, I call it the vitality curve.
00:13:53.020The desire to have children, I think, is bumpy.
00:13:56.900I think there are people at those ages, when they get through college, two years of career, when they get to 30, when they get to 35.
00:14:03.520I think there is bumpiness in the desire of kids around certain ages.
00:14:09.060But there's a greater force that overrides everything.
00:14:13.000So to put it in context, when you model this, again, 39 economies.
00:14:21.280I have to say economies because it includes Taiwan.
00:14:23.940It's a wide, diverse set of countries in East Asia, North America, almost all of Europe.
00:14:30.140When you put all this together into a database, all of this data, you get the same smooth curve and you get predictability that around 94% of birth rates are related to that central age, that vitality curve.
00:14:48.640Only 6% relates to taxes, family policy, the economy, culture, anything else.
00:14:56.220You can tweak it a little bit up and a little bit down.
00:14:58.800But to me, the takeaway for policymakers is that if you ignore the average age of parenthood and only focus on helping everybody have children, the chances of success are small.
00:15:14.840And I'll say one more thing, and this is an irony to me.
00:15:17.620The more you do to help people have IVF or delay parenthood in any way, the lower the curve goes.
00:15:26.940So overall, IVF, of course, great for many people, of course.
00:15:30.920But the more you kind of encourage later parenthood, this curve started like this and anchored at a young age because people are still having kids and teenagers, so it's anchored.
00:15:42.280And as it stretches, you take the life out of society.
00:17:15.160At which point your partner knows you looking elsewhere, and he or she's gone somewhere else.
00:17:19.460When you have a concentrated time span, when everyone's on the same page, it is easier, in technical terms, there's less entropy, less disorder, when people are pair bonding, matching at a younger age.
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00:19:06.260Stephen, you know, when I was watching the doc and I was reading your data, it reminded me of a book that I read a few months ago called Adventures in the Screenwriting Trade by William Goldman.
00:20:57.960But if we're to go back, if we are, if we are, it kind of means creating this turbulence where you're trying to, you're almost trying to tell all the over 30-year-olds,
00:21:09.180like, you go and do your own thing, date with each other, figure it out, while you're trying to have some.
00:21:14.260And I never use the word encouragement.
00:21:16.580It's up to people to have kids if they want them.
00:21:19.700No one should force anyone to even contemplate children.
00:21:24.100But there are many young people who do want family.
00:21:26.660And given the risk of unplanned childlessness, but having those two things at the same time, I've seen it done once in Hungary in a limited way, where you have had policies that have created this bubble in 25-year-olds and younger having children in Hungary.
00:21:44.940And that's probably the most interesting thing happening in demography right now.
00:28:39.100And, I mean, like I said, the dock is brilliant and incredibly powerful.
00:28:44.280And that was one of the moments that really hit home with me.
00:28:48.500The other one that hit home with me particularly was the amount of schools that were closed.
00:28:55.660As somebody who used to teach and you're being surrounded by kids and the energy that kids bring and the liveliness and just seeing you in a deserted playground.
00:29:07.740And then you said that school closed in 2006 and you showed the photograph of a boy being taught on his own.
00:29:16.580It made me feel an almost visceral pain.
00:31:44.460This is a Catholic country where fertility is celebrated.
00:31:49.460And, you know, when I spent a lot of time, I'm not in Brazil, but in Venezuela, it seemed to me that I was surrounded by children and, you know, young people.
00:31:58.980And it was a vibrant, energetic society.
00:32:02.000Yeah, I think that shocks most people.
00:32:03.220I actually spent three weeks filming in six countries just because I had to see it, because I knew people wouldn't believe it.
00:32:09.600And yet, if you go back to Italy 40, 50 years ago, it would have been the same.
00:32:15.700No one would have believed Italians would stop having big families and birth rates would crash.
00:32:20.060Now it's happening in Latin America, and it's about to happen.
00:32:22.400It's already well underway in India, particularly southern India.
00:32:27.600You don't really notice that people aren't having kids.
00:32:29.200Well, change is nothing from a tent, a few schools closed, but not a big deal in the initial phases.
00:32:34.340It takes time for us to notice, which is part of the problem.
00:32:37.540But, yeah, Latin America, Latin America has a bigger problem than the West, much bigger problem, because the West and the Far East got wealthy before they got old.
00:32:53.440Japan's got reserves, huge national debt, but it's got reserves for a while.
00:32:59.200And perhaps they can use those reserves to help re-engineer society.
00:33:47.520The real impact will be 20-plus years' time, and India is on the exact same path.
00:33:51.640So this being a worldwide problem, let's come back to the conversation we started with, which is, I guess, implied and implicit in what you're saying, to some extent, is the idea that the way we got here is not necessarily the way we'll come out of it, in that even if we address some of the reasons that this has happened, that won't take us to where we want to go.
00:35:10.180If you were to do things like put more money in young parents' pockets, if you do things that open more daycare, baby bonuses, all sorts of things that people think of.
00:35:20.500Well, gender, you know, men doing more at the home, more paternity leave.
00:35:50.500If a new bubble emerges, that allows the people older than 30 to continue doing things as they would have for a time, while something new, a new blossom, if you like, emerges.
00:36:02.300Now, I don't know if people actually really will choose to have children younger.
00:36:06.660If they don't, we've got a real problem.
00:36:08.860This is a civilization ending, but that curve is so locked in with no examples of really how to move it other than hoping for a second bubble at a younger age.
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00:38:43.320I think one of the things I definitely observe is that the average age of people getting together into a serious committed relationship seems to be increasing.
00:38:52.900And I have a lot of friends in America now who are in their 20s who are all married and about to have kids because that is kind of part of their worldview.
00:39:02.920But they are kind of the exception, at least globally.
00:39:05.540But, you know, in the 70s, you still had, to some extent, the one-earner household where the man, stereotypically speaking, would go out to work.
00:39:17.140He could feed the entire family off his income.
00:39:20.640His wife could afford to be at home with the kids.
00:39:23.900And now that is just much more difficult to attain for people.
00:39:27.020So I would say that probably quite a lot of young people that would be happy to have kids if that vision was available to them, which it isn't.
00:39:36.120So wouldn't solving that problem – not that I know how to solve it – but if we solved that, wouldn't that turn this all around?
00:39:41.680I'm not saying that these things aren't important.
00:39:44.640But I am saying there's no evidence they'll affect birth rates.
00:39:49.020But we've never – we've not seen that economic reality be reversed.
00:42:45.760How about taking a year out of high school and focusing on what's important?
00:42:48.900How about taking a year out of college, focusing on what's important?
00:42:52.080How about switching to lifelong learning?
00:42:54.460So a 20-year-old can realistically expect to be graduating first stage of education and getting out into the workforce, choosing a career earlier,
00:43:01.760and maybe having time to actually readjust that career based on lifelong learning, saying that didn't work out.
00:43:07.140What about long-term career sabbaticals?
00:43:10.040What about joining a company and becoming an employee but being able to take a five, seven-year sabbatical?
00:43:18.860You still get a little bit of a salary.
00:43:20.260Yeah, there's some simplifying the economics here for sure.
00:43:23.840But imagine you still are attached to that company, still have the business card, the email address, you go to the Christmas parties, the training sessions, you might even do half a day a week.
00:43:34.340The condition would be that after that sabbatical, maybe you've had one, two, three kids.
00:43:38.820Maybe not, but you have that sabbatical.
00:43:40.820The condition is you have to come back for three years.
00:45:00.240But the one I think that may have had the most traction was if you said, as a young person, I want to have a kid, you would get a mortgage deposit, depending on the size of house you wanted.
00:45:15.060Now, why didn't everybody go for big houses?
00:45:18.080Well, you know, the overall risk is still higher and you don't need that space.
00:45:22.140But if you end up having those number of children, two, three, or four, the deposit's basically cancelled.
00:45:41.200It means, I think we know, I mean, family policies have failed so much worldwide generally that people aren't taking $5,000 and saying, great, let's go to the bar tonight and find someone to kind of deposit that check with nine months from now.
00:46:34.880No one's saying, oh, and by the way, here are some risks.
00:46:37.840And if you really do want four children, the spacing thing about delaying them three, four years might not be for you if you really want.
00:46:44.140Those conversations need to enter into our education system.
00:46:47.120Well, you use the term that you use often, which is unplanned childlessness.
00:46:50.940And I think that's really a big portion of this conversation because I think the overwhelming majority of people, and I include myself in this, just fundamentally do not understand fertility even remotely.
00:47:02.720So can you talk to us a little bit about some of the facts and myths about that?
00:47:08.360And, of course, there's so many people proposing theories that sperm counts are falling and that that's a factor and that women's biology isn't quite as – it happens younger than people might think.
00:47:24.020What I'm saying is that before biology becomes a factor – so biology is a big, big thing – there's another more important factor that takes – it's like a filter, if you like.
00:48:16.820You then have involuntary childlessness, which is quite tightly defined as either a medical reason, maybe there's an illness, a hysterectomy, something happened to one of a couple.
00:48:48.060And it was brought – it's now in an international declaration, 57 nations in Porto two weeks ago.
00:48:55.620I worked with an Austrian MP, Gudrun Kugler, who included this term, unplanned childlessness.
00:49:01.620And I was there in person to see politicians from the UK, Labour, Liberal Democrat, Conservative, times 57 nations in a clean recession of 300 people unanimously vote to support that resolution, which includes these definitions.
00:49:15.400So childlessness is not about – I think people – someone once said to me, so this is not my analogy, so I'm going to get a cop out if people don't like this.
00:51:54.380So there are people out there trying to block messages, and one of the messages that they're trying to block is educating women about fertility.
00:52:02.540So they're very happy to confuse – I've seen it.
00:52:05.800I was invited to Doha Debates two years ago.
00:52:10.780It never aired because, unfortunately, that series coincided with October 7th.
00:52:16.380And the tone of it, the host was a comedian.
00:52:20.780And once you get comedians involved in things, you know, it was too serious an event, I think.