The global fall in fertility rates has arrived faster and spread further than anticipated. Two-thirds of people now live in countries that have slipped below the replacement rate – 2.1 births per woman – required for a stable population. Last month, India revealed that its fertility rate had fallen to just 1.9. The world’s two most populous nations, which pursued cruel and coercive policies to cut births, both face shrinking populations. China’s fertility rate is now around 1, and births last year fell below 8 million – just over half the number projected when the “one child” policy was axed 10 years ago, and comparable to the total in 1738, when its population was 150 million.

It’s further proof that what was seen as a phenomenon of rich nations has spread far beyond them. East Asia led the way. But Albania and Chile have far lower rates than the US or England and Wales (themselves experiencing record lows of 1.6 and 1.4).

There are reasons to celebrate the shift. People have fewer children when they expect their babies to survive. The sub-Saharan African countries that lead fertility tables with around 6 births per woman, such as Chad and Somalia, also lead child mortality tables. Women’s education and their economic and social empowerment also cut birthrates. The UN now predicts that the global population will rise by around 2 billion, to peak at 10.3 billion in the 2080s – sooner than expected a decade ago. That may not have much impact in easing global heating, but it could help reduce competition for resources.

Yet in Turkey, Hungary and elsewhere, reversing fertility decline is presented as a matter of national survival. Governments are not only subsidising childcare and sponsoring dating apps but also taxing contraceptives and cracking down on LGBTQ+ communities. Financial incentives appear to have short-term and limited impacts. The US has shown how abortion bans not only deny women their rights and force some to have children against their wishes, but increase maternal and infant mortality and deter other women from having wanted children.

Last year, the United Nations Population Fund found, in a survey of 14 countries, that “alarmingly high proportions” of adults were unable to have the children they hoped for. Almost two in five said financial limitations had affected or would affect the size of their family; one in five cited concerns about the future, such as the impact of climate change.

Supporting those who want to have more children with family-friendly policies and affordable housing is welcome in and of itself and may bring a softer demographic landing. Sharp falls are harder to manage than slow declines. Ageing populations will have to be supported – and cared for – by a shrinking number of workers. But people are likely to be healthier and better educated – improving productivity and extending working lives. Technology may also help to fill the gap.

Just as Africa’s population boom does not guarantee prosperity, so the impact of falls will depend on how they are managed. Countries must wrestle with profound social and political questions, including whether they are willing to accept and able to attract migrants; whether domestic political systems need to be redrawn as national populations are reshaped; and whether young people see a social contract worth sustaining. Governments should focus on understanding how their populations are changing, and preparing for that, rather than making futile attempts to reverse the decline.

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