India's new birth report just revealed a TFR of 1.88, a little below replacement.

But unlike most countries, 🇮🇳 does not have a crisis of low births. With its young population, India had 23 million births, 3x more than any other country.

A look at how India is different. 🧵!

https://twitter.com/BirthGauge/status/2057351376192131166

South Asia is the one region where marriage remains almost universal even as it has collapsed nearly everywhere else. Why? Arranged marriage.

In China, Korea and Japan, arranged marriage was common but became rare.

In India by contrast, arranged marriage remains the norm. 2/7

A shocking new study finds that the desire for children has collapsed among young people in China.

In the most recent data some 32% of 18–24-year-olds, and nearly half of young women, said they don't want any children at all. 🧵.
Fertility desires have long been taken for granted. Even as fertility has dropped, the desire for children seemed strong.

If birthrates were too low, many argued it was only because of structural barriers to having children, like housing and childcare. 2/7

Early birth data for 2026 is out. Europe and Asia are moving in opposite directions.

Many European countries are showing stabilization and even a modest recovery in births.

In East Asia, meanwhile, births are plunging by double digit percentages to extremely low levels. 1/4

https://twitter.com/BirthGauge/status/2051747059317809469

In Europe, Finland, Sweden, the Netherlands, Germany, Switzerland, Spain, Portugal and Greece are all showing an absolute increase in births in 2026.

That is impressive considering that the average age in the EU is 45 and there are fewer women of childbearing age every year. 2/4

A paper published today argues that women's liberation led to collapsing fertility around the world.

Using US data, the authors show 58% of women's sexual relationships are with the most promiscuous 10% of men.

But most of these relationships are short term and childless. 🧵.

Women's freedom, widely viewed as positive around the world, is strongly associated with lower fertility, the authors find (r=.81).

Many forces have led women to pursue short-term rather than long-term mating strategies. But most of these partnerships don't lead to kids. 2/5

HOW ONE MAN REVIVED A NATION
The population pyramid of Kazakhstan is unlike any other in the world. Birthrate decline was stopped and reversed, even as the country grew rich.

Nursultan Nazarbayev led 🇰🇿 for 27 years from its founding in 1991 and got it to grow again! 🧵!

Kazakhstan's population pyramid inverted in the mid 1980s as the number of births declined sharply and fertility fell below replacement in the 1990s.

But then births sharply recovered and Kazakhstan experienced a baby boom lasting almost 30 years even as it's GDP grew 15x! 2/7

A study in Sweden found that firstborn children tend to have more children of their own than those that came later in the birth order.

Why? It is likely because older siblings had exposure to babies growing up, while younger siblings did not. 🧵.

https://twitter.com/uaustinorg/status/2039351993316102448

The large study of siblings (N = 1.5 million) found firstborns tend to have significantly more children than those that came later.

The effect is especially strong for women. When girls have a chance to help with little ones, they have much stronger family desires later on.
2/4

A new map shows the last time each country in Europe reached replacement fertility.

Most western European countries, including the UK, France, Germany and Italy haven't had replacement fertility in more than 50 years.

This is the main reason for Europe's stagnation. 🧵. This map shows the sobering fact that once a country falls below replacement, it almost never bounces back.

Eastern Europe did not fall below replacement until the 1980s but has had exceptionally low fertility over the past 25 years. 2/4

A big fail in the New York Times today with the claim that "31 is the new 21."

The Times leads readers to believe today's young women will make up lost fertility in their 30s and 40s.

But all evidence indicates they will not. 🧵.
First, the Times is ignorant of what recent research shows about age and infertility.

A big 2023 study of three million women by Geruso, Spears and LoPalo found that the ability to get pregnant is much lower in the 30s than the 20s.

So unfortunately, 31 is not the new 21. 2/4

A recent study found that giving men a pay raise led them to have more children, while giving women a pay raise led them to have fewer children. 🧵.
For women, the effect of a pay raise was significantly reduced future fertility. A pay increase at 25 was associated with a large decrease in fertility at age 30, regardless of the skill level.

For men, a pay increase was associated with persistently higher fertility. 2/4

A newly published paper found pronatal policies only worked when supported by culture.

"Maternity benefits increased fertility only among women who grew up in religious families" in the Baltics.

This could explain why many pronatal policies have not boosted fertility more. 🧵.
In 1982, there was a big expansion in child benefits in Estonia, Latvia and Lithuania including maternity leave wage benefits, a cash payment for birth and 18 months of job protection.

Five East European countries with comparable economic systems did not get the benefits. 2/5

A new study finds that work-from-home raises fertility more than any conventional family policy.

"Estimated lifetime fertility is greater by 0.32 children per woman when both partners WFH one or more days per week as compared to the case where neither does." 🧵.
In this chart, a large effect is clearly seen, with fertility higher when either partner has some work-from-home and highest when both do.

The authors say this is not due to selection because fertility rose among those that unexpectedly got WFH, compared to those that didn't.

On this Christmas, we can reflect how Christianity was able to grow out of the ashes of collapsing Rome.

Scott Alexander reviews Rodney Stark's The Rise of Christianity and describes how the new faith won out by valuing women and children.
Important 🧵!
Much like our world today, Pagan Rome faced terrible birthrates.

Sex-selective infanticide was the norm. Women were not valued and many men just wanted to stay single.

It got so bad that Roman General Macedonicus proposed forcing people to marry! 2/7

Fertility and child populations are collapsing in left-leaning areas.

A new analysis by @FamStudies documents how marriage and childbearing are in steep decline among young liberals.

Given political trends, we may see big declines for national birthrates ahead. Important 🧵.
Media headlines across left-leaning media tell the story of growing anti-marriage and anti-child attitudes. 2/6

The Cradle of Europe, Fading Fast
Italy is at the center of our world, with more cultural and religious heritage than anywhere else on Earth.

How did Italy, once famous for its family culture, become the most aged country in Europe and what could turn things around? 🧵!
Italy's fertility in 2025 is just 1.12 births/woman, one of the lowest in Europe.

There are many statistics that help explain why the birthrate in Italy is so low, but one astonishing number stands out: Some 52% of Italian men aged 25-34 still live at home. 2/8

It has gone unnoticed that the most infamous school shooting in US history, the Sandy Hook shooting, may have had its origin in far left, antinatalist ideology.

Adam Lanza's recordings, found in 2021, expressed strong interest in antinatalism as well as p*dophilia. 🧵. Adam Lanza's YouTube channel "CulturalPhilistine" was not discovered until September of 2021, some 9 years after the shooting, after public interest had waned. At the time of the shootings, Lanza's motives were a mystery.

The YouTube channel contained only audio but matched recordings of Lanza's voice. The strongest evidence that the channel belonged to Lanza is that it includes long readings from a 35-page college application essay that Lanza had submitted on the topic of p*dophilia.

Lanza's first and fourth recordings were on the topic of antinatalism and "antinatal" appears 24 times in the transcripts.

"Life is suffering" appears in the title of another recording, and this is a key part of antinatal ideology. 2/6

One of the strongest predictors of fertility for countries is how many children most people consider to be ideal.

This shows that values around children drive birthrates strongly. We also see that actual fertility (1.48) is far below what people say they desire (2.36). 🧵

https://twitter.com/BirthGauge/status/1961174400516198542

Notice how strongly fertility ideals predict actual fertility, with the ideal number of children predicting 64% of a country's TFR.

Why does the US have a higher birthrate than Europe even though family policies are much more generous in the EU? A stronger desire for kids. 2/5

Published today, an important paper proposes a framework dividing total fertility rate into two component parts:
TFR = Total Maternity Rate (TMR) x Children per Mother (CPM)

This lens shows that virtually all recent declines in fertility were due to increasing childlessness. 🧵

Demographer @StephenJShaw realized that these two components of TFR, the total maternity rate (or equivalently, the childless rate) and children per mother move quite independently of each other.

That means one gets much more information from looking at both parts together. 2/6

All of China has low birthrates, but northeastern China has the lowest fertility of any region in the world, lower than South Korea. Why?
It was in these regions that the one-child policy was most rigorously enforced, completely wiping out natalism from the culture. 🧵 China's One Child Policy is gone now, and since July 2021, all birth limits have been removed.

But while the OCP was in force, millions of pregnant Chinese women experienced the tragic brutality of forced abortion, which I explored in this thread (2/5):

https://x.com/MoreBirths/status/1824662321358053877

Colombia has had one of the fastest fertility drops in the world, from 2.57 births/woman in 2000 all the way down to 1.2 in 2024.

How can it be that Colombia, with a GDP of 7K per year, has a fertility so much lower than the US? And why is this happening across Latin America? 🧵

https://twitter.com/JesusFerna7026/status/1945805119561363929

Colombia recorded only 445,000 births in 2024, way below UN projections of 701,000 births, for an official fertility rate of just 1.06 births per woman, and just 0.84 in Bogotá. (The true rate may be a little higher with unregistered births.)

Why such a dramatic collapse? 2/10

On this Father's Day, let's think of young guys and the future.

How can young men, most of whom really want children one day, boost their odds of achieving fatherhood?
🧵! Perhaps the first thing for young men to focus on is gaining income and building a career.
There is a strong positive relationship between a man's income and the number of children he will have.
This was true in the past and it is still true today, all over the world. 2/9

UPenn economist @JesusFerna7026 just gave an important talk called The Demographic Future of Humanity.
Key points:
(1) Birth data is much worse than the UN reports,
(2) UN projections are absurdly rosy,
(3) Economic growth will be low, and
(4) Immigration cannot fix this.
🧵 First, Fernández-Villaverde notes that in country after country, the UN's birth figures are far higher than what those countries officially report.

For example, the Colombian government reports births 25% lower than what the UN claims. In Egypt and Türkiye, the gap is ~12%. 2/8