Fertility rates cut in half since 1950 - but the population is still growing

The total fertility rate – the average number of children in the Netherlands.

Meanwhile, the global population has tripled since 1950, from 2.6 billion people to 7.6 billion, the report says. An average of nearly 84 million people have been added to the Earth's population every year since 1985.

"As women have gotten more educated and participate more in the workforce and they get access to health services, no surprise, fertility has come down tremendously," said study author. Christopher Murray, director of the Institute for Health Metrics and Evaluation at the University of Washington. "And it comes down faster in younger women."

Other factors have been shown to predict falling fertility rates, including better infant survival rates and later marriage.

"The age at which women are getting married is increasing," he said. James Kiarie, coordinator for the World Health Organization's Human Reproduction Team in the Department of Reproductive Health and Research.

"Marriage is one of the biggest drivers of having children all over the world," said Kiarie, who is not an author on the new report.

'The world is really divided'

While total fertility rates fell across 195 countries and territories in the data, they were split roughly between the above and below, Murray said. "Replacement" describes the total fertility rate "at which population is no longer alive, assuming no migration.

For example, a woman in Cyprus had one child on average in 2017, while a woman in Niger had 7.1. This range is lower than 1950s, in which total fertility rates ranged from 1.7 live births in Andorra to 8.9 in Jordan.

"The world is really divided into two groups," Murray said. "In a generation, the issue is not about population growth, it's going to be about population decline or relaxing immigration policies."

In countries that want to boost fertility rates, the creation of financial incentives for families, including parental leave, has been shown to have a small effect, Murray said. Only 33 countries, largely in Europe, were falling in population between 2010 and 2017, according to the report.

"The country that is most concerned about this is China, where the number of workers is now starting to decline, and that has an immediate effect on economic growth potential," Murray said. "In a place like India – that is still a replacement, but that is just a dramatic change."

That does not mean the global population will soon reverse course. A United Nations report last year predicted that the world population would swell to 9.8 billion by 2050 and 11.2 billion in 2100. That report forecast that half of the expected growth between 2017 and 2050 is likely to occur in Africa.
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In just the past years, Kiarie said, parts of Africa and Asia have lowered fertility rates. The countries that have declined are the lower rates of contraception, where the introduction of family planning made a more significant impact, he added.

"There's a rapid progress, but I think in terms of … the areas that have the greatest need for family planning, it's still pretty in Africa," he said.

Lifestyle continues to kill millions

Thursday's report comes alongside six others, funded by the Bill & Melinda Gates Foundation, on the global burden of disease. The findings include rising prevalence of obesity in nearly every nation, idling or worsening mortality rates in some countries, and high burden of non-communicable diseases, contributing to nearly three-quarters of deaths worldwide in 2017. The top risk factors were high blood sugar, high blood pressure, high body mass index and smoking.

Lifespans have also gotten older on average since 1950, climbing from 48.1 to 70.5 years for men and women from 52.9 to 75.6 years, according to the study. However, the study authors say that just because women live longer does not mean they are living in better health.

An editorial published by The Lancet points out that countries in the world are falling behind the United Nations 'global health goals in some way, and the study' should be an electric shock, galvanizing national governments and international agencies. avoid the imminent loss or hard-won gains but also adopt a fresh approach to growing threats. "

When it comes to fertility rates, Kiarie said that the UN goals are the number of children they want, and that is what they choose. "What is key for that is to be there, in the women's hands."

What often gets lost in discussing fertility statistics and population numbers, Kiarie said, is the focus on individual people, their desires and how to empower them to achieve those goals.

"How can we ensure that people do what they think is right for themselves?" he asked.

CNN's Yemisi Adegoke contributed to this report.