"In 2020, the growth rate of the global population fell under one per cent per year for the first time since 1950," notes the report, released on Monday.

Despite regional differences, John Wilmoth, director of the UN's Population Division, sees opportunities in this development for developing countries.

Alongside fighting poverty and hunger, there could be benefits in education, because fewer children means more attention per child.

"When the average family size goes down, it becomes possible for both families and societies to invest more in each child and to raise the quality of the education and develop the human capital of the population," Wilmoth told dpa.

At the same time, lower birth rates mean an ageing population overall and a larger proportion of people being at an age where they need assistance.

This will also be affected by an increase in life expectancy from 72.8 in 2019 to 77.2 in 2050, the UN estimates.

More and more high-income countries will slip into negative population trends, like Japan has already done today. To maintain a stable growth rate, countries like Germany would need to rely on migration.

Despite the slowdown in growth, the UN expects the world's population to pass the eight billion mark before the end of the year - probably around November 15.

Australian Associated Press