14 Comments
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Sebastian Jensen's avatar

The effect within individuals is a lot weaker than the effect between nations, which suggests confounding or large group-level effects.

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Sebastian Jensen's avatar

The correlation between IQ/education and fertility is also weaker in highly educated nations, which could explain why the effect is attenuated past that point. Some of it is because education causes income which causes fertility, but the education itself makes people have less children than they otherwise would.

https://www.econlib.org/archives/2011/06/kids_are_normal.html

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Dave's avatar

It’s just the prime time age range thing. It also lines up with the 10 yr estimate.

•Girl turns 18, goes to college for 10 years, now she’s 28.

•Amish girl or whatever culture turns 18, starts having kids at peak fertility. At 28 yrs old she might have 4 kids already.

The question and ‘mystery’ gets a lot simpler if you use the analogy of elite male sportsmen, let’s call them football players. The prime time for them is 20-30 and they’re basically washed up starting from 31 and getting geometrically more severe with each additional year. It’s just the biology. No one argues it. When it’s women though people lose their minds.

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Reports99's avatar

Not so sure on your interpretation here. The big story is that increased education is indeed associated with decreased fertility. That little uptick doesn't seem terribly important, and yet you hang much of your interpretation on it. Even if we allow it, the question is how to interpret it. I think we know that there can be a strange hypocrisy or contradiction among the elite - they champion progressive social programs that serve to destroy the family, yet they themselves invariably enjoy the benefits of traditional family structures. I can well imagine that those women who earn MAs and PhDs will recognize the need for traditional families, whereas those with merely the BA level (the vast majority) get psyoped into thinking that career will satisfy them.

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Performative Bafflement's avatar

There is data on this, and indeed, grad degree obtainers (1.4 - 1.5) do have higher fertility than undergrad (~1.3).

https://imgur.com/a/GqecW0A

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devlin's avatar
4hEdited

You are more or less predicting the dynamic incapacitation effects and how women have children latter due to education in semi-mechanical way by shifting the decision into the future bc a government makes them sit through classes. It can lead to lower cohort fertility if it's not realized down the road, but leads to longer time between cohorts for sure.

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João Correia's avatar

I think part of the post covid fertility crash is just migrations to big western countries and city centers, so there is that offset effect.

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Anatoly Karlin's avatar

> Female education does seem to cause lower fertility, but stops having an effect around 10 years of schooling.

If you're going to go the eliminating women's education route to raising fertility, you would have to go way beyond universities, i.e. literal "White Sharia" meme LOL.

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Vasubandhu89's avatar

From a recent Noah Smith post:

Some studies in poor African countries find that sending girls to school for an additional year does reduce childbearing.... But this estimate might not actually hold for higher levels of schooling; it doesn’t really tell us what happens when you go from, say, 9 to 14 years of female education. Chen (2022) looked at an expansion of higher education in China, and found that it actually raised birth rates by a significant amount. Monstad et al. (2008) found zero effect of education on fertility in Norway, and Cummins (2025) find zero effect in England.

https://www.noahpinion.blog/p/at-least-five-interesting-things-4c7?utm_source=post-email-title&publication_id=35345&post_id=167476849&utm_campaign=email-post-title&isFreemail=true&r=39c1o4&triedRedirect=true&utm_medium=email

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PR's avatar

It is absurd to deny that more women working is not related to this decline, starting in 1980.

Are there other causes? Yes. Feminism and hate speach against males being also one.

After COVID is also after the MeToo pick, which happened only few years before. So having in mind that It takes around 5 years from the couple formatio till the time you have a kid, you have your answer to the post COVID decline.

There is only 1 solution: raise the status of men.

Which, btw, is fair.

Men cannot longer account 40% of degrees. Its a shame for the "equality view" of feminism. And also for fertility rates.

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John Hines's avatar

Great data, great graphs. Need to read it again, more carefully. Thanks

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RawValueStack's avatar

I will have to Look at raw Data myself later, but why focus so much on the upward tail? It’s doesn’t matter at some point. These females Are basically housewives who have no desire to work anyway. For them it’s just a hobby to be in education to catch wealthier men. The problem is that people don’t have children at 20-25. Which is the steepest point in the graph.

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Performative Bafflement's avatar

It's also a problem, because those are literally peak fertility years, and if you wait until your early thirties to have your first kid (which is the median in the US and UK), you'll have burned through ~60% of your cumulative fertility to that point (area under the curve before age 30 in below graph):

https://imgur.com/a/DCff1fl

Graph from Geruso, Age and Infertility revisted (2023)

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Alistair Penbroke's avatar

Why would social media be any different post COVID? Social media has existed since 2005 or so. Seems more likely to be vaccine related.

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