101 Facts About Ageing #38: Living Longer With Fewer Children

As Daniel Patrick Moynihan, an American sociologist, politician, and diplomat once said: “Everyone is entitled to his own opinion, but not his own facts”. And we wholeheartedly agree. A shared set of facts is the first step to building a better world with longevity for all. In that spirit, we are creating a series that covers 101 indisputable facts about ageing, health and longevity.

Throughout the world, the number of children per woman inversely correlates with life expectancy at birth. Indeed, a country’s life expectancy at birth is the best predictor of the average number of children per woman. Economic prosperity, mechanisation, higher levels of education and improved healthcare reduce the need for having larger numbers of children, leading families to instead focus on seeking better quality of life for their offspring, usually beginning with improved nutrition.

As quality of life has risen and birth rates have declined, many countries have dropped below the ‘replacement level’ of fertility, which is about 2.1 children per woman. According to the UN, about half of the world’s population lives in countries that are at or below replacement level.