Scientists from the Institute of Health Metrics and Evaluation (IHME) have warned of a looming global fertility crisis that could reshape population dynamics by the end of the century.
The findings, published in The Lancet on Wednesday, suggest that fertility rates are plummeting in almost all countries below the levels required to sustain current population numbers.
Stein Emil Vollset, senior researcher and co-lead author of the study from the Institute for Health Metrics and Evaluation (IHME) at the University of Washington, Seattle, emphasizes that this trend will sharply contrast nations experiencing a "baby boom" and those facing a "baby bust."
Low-income countries, already grappling with economic and political instability, are expected to see a surge in births, while wealthier nations witness plunging birth rates.
The study, which draws on data compiled between 1950 and 2021 as part of the Global Burden of Diseases, Injuries, and Risk Factors Study, paints an alarming picture.
It predicts that by 2050, 76 percent of countries and territories (155 out of 204) globally will record fertility rates lower than replacement levels, a figure expected to soar to 97 percent (198 countries) by 2100.
According to the researchers, over a third of live births are anticipated by the end of the century in low- and lower-middle-income countries, with more than half concentrated in sub-Saharan Africa.
This shift reflects a global fall in the average number of children born per woman, plunging from roughly 5 in 1950 to 2.2 in 2021.
The implications are profound. With fertility rates dropping below 1.1 children per woman, nations such as South Korea and Serbia face significant problems of workforce decline.
Vollset stressed the urgency for resource-limited countries to support rapidly growing populations amid precarious political, economic, and environmental conditions.
Meanwhile, in high-income countries, declining fertility rates are partly a result advancements in women's education and employment opportunities — but also underscore the need for improved access to contraception and education in other regions.
Natalia Bhattacharjee, one of the study’s lead co-authors, suggests that as populations dwindle, countries may increasingly rely on mass immigration in a bid to sustain economic growth.