Will global birth rates finally start rising again? Researchers say maybe not

It’s no secret: the world’s birth rates are falling.

This has been happening for decades, as child deaths have declined, access to contraception has expanded, the cost of raising a child has risen, women’s education has increased, fewer people are getting married and multiple crises occur simultaneously.

But they can’t fall forever, right?

Well, they could continue to drop, a new analysis of years of related data from researchers at the University of Texas at Austin and New York City’s Hunter College shows.

“We show that there is no robust evidence for a systematic fertility rebound, or for a stable equilibrium point at any fertility level conventionally assumed. Instead, where and when fertility has fallen low, it has tended to keep falling,” the authors wrote this month in a working paper published by the National Bureau of Economic Research.

That appeared to be true across a range of data sources, including United Nations data on total fertility rates, the online Human Fertility Database project and fertility rates in regional and local data in Japan, India and the U.S.

The results in the paper – which has yet to be peer-reviewed – suggest that stopping declining fertility would be a departure from the average trends, though they concluded that there is not enough data to ”draw any firm conclusion” yet.

Some separate and previous projections assumed a rate at which fertility rates rebound and stabilize, they noted, saying that these assumptions should be understood as hypothetical.

“We reconcile these results with a prior literature that documented fertility reversals among some low-fertility countries in the early 2000s,” the researchers said. “Our findings provide an empirical basis for reexamining the equilibrium and rebound assumptions embedded in widely used population projections.”

However, the authors acknowledged that further research could find factors their own did not take into account.

Whatever the future holds, population dynamics have already shifted in the U.S.

For one, the U.S. population is aging – the Census Bureau says older adults will make up 23.4 percent of the population by 2060 – as births have plummeted by nearly a quarter since 2007, according to federal data.

The number of deaths outpacing births in more than half of states, the bureau says.

However, population growth has dramatically slowed largely due to declines in migration, now falling to 0.5 percent between July 2024-2025, a bureau release from January said.

Should trends continue, America’s population could even shrink down the line.

It’s not yet clear what that would mean for Americans, but changes in immigration policy could change that, Qian Cai, director of the Demographics Research Group at the University of Virginia’s Weldon Cooper Center for Public Service, suggests.

“Unless immigration increases substantially over the next two decades, U.S. population growth is expected to remain significantly slower than in the past and at historically low levels,” she said in July.