Most of the world is below replacement rate (~2.1 TFR), the rest will get there in a decade or two. Educated, empowered women delay having children, have less children, or no children. Holds across both developed and developing countries.

https://www.pewresearch.org/short-reads/2025/08/15/5-facts-a...

https://www.sas.upenn.edu/~jesusfv/Slides_London.pdf

https://www.visualcapitalist.com/cp/mapped-countries-by-fert...

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ericd an hour ago | parent | next [-]

Right, it looks pretty catastrophic for some areas (eg South Korea) if it doesn’t stabilize.

But I’m also skeptical of anything that extrapolates anything related to human behavior out 75 years.

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toomuchtodo an hour ago | parent [-]

Once you hit ~1.5 TFR, low fertility trap kicks in.

> Demographers in the early 2000s coined the “low-fertility trap,” hypothesizing that a series of self-reinforcing economic and social mechanisms make it increasingly difficult to raise the fertility rate once it dips below a certain threshold. The academics posited that lower fertility results in increased individual aspirations for personal consumption but at the same time it also results in an aging population and less job creation—and thus greater pessimism about the economic future—which in turn disincentivizes having more children. Moreover, as the average family size grows smaller and smaller generation after generation, the social norm of an ideal family size shrinks, too. These forces together lead to a persistent “downward spiral” for the fertility rate that can be impossible to reverse.

> China’s not the only country in the region or the world facing this kind of demographic crisis. Fertility rates across developed nations globally have almost uniformly dropped over the last few decades. China’s neighbors Japan and South Korea have among the lowest, and policymakers there have invested billions of dollars and pondered uniquely targeted policies, respectively, to try—so far unsuccessfully—to get young people to have more children.

https://time.com/6306151/china-low-fertility-trap-birth-rate...

https://onlinelibrary.wiley.com/doi/10.1111/j.1728-4457.2005...

	▲	felipeerias 5 minutes ago \| parent [-]
		Several European countries have already fallen in this trap. As pensioners comprise an increasingly large fraction of voters, pandering to them becomes far more politically attractive than investing in the future.

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alex43578 2 hours ago | parent | prev [-]

The world, yes, but specific niches no. Look at the Mormons, or Nigeria, or Somalis in America at 3x the US birthrate.

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toomuchtodo 2 hours ago | parent [-]

Latter-day Saints are having fewer children. Church officials are taking note - https://www.npr.org/2025/10/31/nx-s1-5535654/latter-day-sain... - October 31st, 2025

> Dallin H. Oaks, the newly appointed prophet and president of the church, said that while birth rates within the church are higher than national numbers, they've still declined "significantly."

> Catholic University of America demographer Stephen Cranney crunched the numbers on the religion's families. In 2008, about 70% of Latter-day Saint women ages 18-45 had at least one child at home. In 2022, that number was 59%, a rate of decline mirrored in the American population at large.

Any uptick in birth rate in the US from first generation immigrants quickly reverts to the mean for subsequent generations.

The Fertility of Immigrants and Natives in the United States, 2023 - https://cis.org/Report/Fertility-Immigrants-and-Natives-Unit... - May 1st, 2025

Reproductive freedom (or rather, freedom from reproduction, and its costs and burdens) is culturally contagious.

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alex43578 2 hours ago | parent [-]

"Latter-day Saints still have more children"

That study has 7 to 12% error ranges for the LDS group. Even with that, the share of LDS women with a child at home is 50% more than non-LDS. Lastly, there's a huge difference in rate of decay when a group is at, above, or below replacement rate. If everyone's declining, but they're declining far slower, that still proves my point that the composition of these communities in 80 years could be far different if current rates hold.

	▲	toomuchtodo 2 hours ago \| parent [-]
		Utah has one of the most expensive housing markets in the country, and average children per women is 1.8 in the state. It’s always hard to predict the future, but I argue the evidence is clear LDS fertility rates will rapidly coalesce with others within the next few years, maybe faster if young followers leave the church faster. Utah slides to No. 10 for fertility in U.S. - https://www.deseret.com/family/2025/04/07/utah-drop-fertilit... - April 7th, 2025 US Gen Zers and millennials are leaving the LDS church, data confirms - https://religionnews.com/2025/12/10/us-gen-zers-and-millenni... - December 10th, 2025 > In 2007, according to Pew, the LDS church retained 70% of childhood members in the U.S. (n = 581) In 2014, that was 64% (n = 661), and in 2023–24 it had declined still further to 54% (n = 525). > That 54% current retention rate looks better than the GSS’ 38%, so that’s potentially good news for LDS leaders. But once again, we’re witnessing a clear drop from the fairly recent past. Both major U.S. surveys that track childhood affiliation are saying that more people are leaving than used to. > What’s more, this is being driven by younger adults. In the general population, younger adults are noticeably more likely to have no religious affiliation than older adults — either because they’ve left religion or they grew up without one. It shouldn’t surprise us that it’s true in Mormonism as well. So, the cohort leaving the church the fastest are the ones with fertility. What does this do to LDS fertility rate trends? It likely bends them downward.