The number of children born per woman has halved globally since 1950, according to a study published in The Lancet.
Researchers found that although the global population has roughly tripled from 2.6 billion to 7.6 billion, the fertility rate has dropped from 4.7 live births per woman in 1950 to 2.4 in 2017. As well as women having better access to education, employment and health services, the fall in fertility rate has been attributed to better infant survival rate and an increase in the average age of marriage.
'The lower rates of women's fertility clearly reflect not only access to and availability of reproductive health services, but also many women choosing to delay or forgo giving birth, as well as having more opportunities for education and employment,' said study author Professor Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington in Seattle.
These figures are a global picture and unsurprisingly mask the vast differences seen between nations. The lowest fertility rate was reported in Cyprus, where on average women are giving birth to one child in their lifetime. However, in Niger the fertility rate was as high as seven children per woman.
'These statistics represent both a "baby boom" for some nations and a "baby bust" for others,' Professor Murray said. 'The world is really divided into two groups. In a generation, the issue's not going to be about population growth. It's going to be about population decline or relaxing immigration policies.'
Professor Murray told the BBC: 'On current trends, there will be very few children and lots of people over the age of 65 and that's very difficult to sustain global society. Think of all the profound social and economic consequences of a society structured like that with more grandparents than grandchildren.'
Dr James Kiarie, coordinator of the World Health Organisation's Human Reproduction Team, who was not involved in the study, told CNN: 'What often gets lost in discussing fertility statistics and population numbers is the focus on individual people, their desires and how countries can empower them to achieve those goals...what is key is for that ability to be there, in the women's hands.'