A groundbreaking study published in The Lancet unveils alarming projections about the future of global fertility rates and livebirth patterns, painting a portrait of a world on the brink of dramatic demographic transformation.
By the year 2050, the study forecasts that over three-quarters of countries worldwide—155 out of 204—will face fertility rates insufficient to sustain their populations over time. This dire trend is expected to worsen by 2100, with a staggering 97% of countries—198 out of 204—projected to fall below replacement fertility levels.
The research, led by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington’s School of Medicine, highlights pronounced shifts in the distribution of livebirths, with low-income regions poised to experience a significant surge. Sub-Saharan Africa, in particular, is forecasted to account for a striking 54% of all global births by 2100, underscoring the urgent need for enhanced access to modern contraceptives and female education in these areas.
Professor Stein Emil Vollset, senior author of the study, warns of the profound economic and societal implications of these demographic shifts. “We are facing staggering social change through the 21st century,” he remarks. “As most of the world contends with the serious challenges of a shrinking workforce and ageing populations, resource-limited countries in sub-Saharan Africa will be grappling with supporting the fastest-growing population amidst political and economic instability.”
Declining fertility worldwide – only six countries with fertility rates above replacement level in 2100
The global TFR has more than halved over the past 70 years, from around five children for each female in 1950 to 2.2 children in 2021—with over half of all countries and territories (110 of 204) below the population replacement level of 2.1 births per female as of 2021. This trend is particularly worrying for places such as South Korea and Serbia where the rate is less than 1.1 child for each female. But for many countries in sub-Saharan Africa, fertility rates remain high—the TFR of the region is nearly twice the global average, at four children per female in 2021. In Chad, the TFR of seven births is the highest in the world.
Over the coming decades, global fertility is predicted to decline even further, reaching a TFR of around 1.8 in 2050, and 1.6 in 2100—well below the replacement level. By 2100, only six of 204 countries and territories (Samoa, Somalia, Tonga, Niger, Chad, and Tajikistan) are expected to have fertility rates exceeding 2.1 births per female. In 13 countries, including Bhutan, Bangladesh, Nepal, and Saudi Arabia, rates are even predicted to fall below one child per female.
The TFR in Western Europe is predicted to be 1.44 in 2050, dropping to 1.37 in 2100, with Israel, Iceland, Denmark, France, and Germany expected to have the highest fertility rates at between 2.09 and 1.40 at the end of the century. Rates are projected to be much lower across the rest of Europe and parts of Asia.
Most of the world is transitioning into natural population decline (when the number of deaths exceeds the number of live births); just 26 countries are still projected to be growing in population in 2100 as livebirths continue to outnumber deaths, including Angola, Zambia, and Uganda [1].
“In many ways, tumbling fertility rates are a success story, reflecting not only better, easily available contraception but also many women choosing to delay or have fewer children, as well as more opportunities for education and employment,” said Vollset.
Dramatic shifts in the patterns of births – with more than half of live births occurring in sub-Saharan Africa by 2100
In the coming decades, the majority of children will be born in some of the most resource-limited regions of the world, with over three-quarters (77%) of live births expected in low- and lower-middle-income countries by the end of the century.
Fertility decline for many countries in sub-Saharan Africa is occurring at a slower pace, and the region is expected to contribute to over half (54%; around 40 million) of the world’s livebirths by 2100, up from around 41% in 2050, and around a quarter (29%) in 2021.
Much of the anticipated decline in the global share of livebirths will be in the six other super-regions—falling, for example, in South Asia —from around 25% (32 million) in 2021 to 17% (19 million) in 2050 and 7% (5 million) in 2100—but is forecasted to rise modestly in the North Africa and Middle East (from 9% in 2021 to 11% in 2100) and the high-income super-region (8% to 10%).
“A large challenge for countries in sub-Saharan Africa with the highest fertility is to manage risks associated with burgeoning population growth or risk potential humanitarian catastrophe,” said co-lead author and Acting Assistant Professor from IHME Dr. Austin E. Schumacher. “The huge shift in numbers of births underscores the need to prioritise this region in efforts to lessen the effects of climate change, improve health care infrastructure, and continue to reduce child mortality rates, alongside actions to eliminate extreme poverty and ensure that women’s reproductive rights, family planning, and education for girls are top priorities for every government.”
The study emphasizes the critical role of policy interventions tailored to the unique challenges faced by both high-fertility and low-fertility nations. While low-income settings require better access to contraceptives and educational opportunities for women to reduce birth rates, high-income economies must implement policies supporting parents and open immigration to sustain population size and economic growth.
Dr. Natalia V. Bhattacharjee, co-lead author of the study, underscores the urgency of global recognition and action in response to these trends. “These future trends in fertility rates and live births will completely reconfigure the global economy and the international balance of power,” she asserts. “Global efforts are crucial in addressing the challenges posed by these demographic shifts.”
The study’s findings underscore the pressing need for national governments to plan and implement strategies to mitigate the emerging threats to economies, food security, health, and geopolitical stability brought about by these seismic demographic changes.
As the world braces for unprecedented demographic shifts, the Lancet study serves as a clarion call for concerted global action to address the complex challenges ahead.