The United Nations has urged developing countries to invest in family planning to cut fertility rates and open a "demographic window" for economic growth.
"There is solid evidence, based on two generations of experience and research, that there is a 'population effect' on economic growth," the UN Population Fund (UNFPA) said in a new report.
UNFPA provides almost $6 billion a year to reproductive health programmes, which include care for pregnant women and newborn babies and prevention of sexually transmitted diseases and HIV/AIDS as well as family planning.
The report, People, Poverty and Possibilities,argued that addressing population concerns was crucial to meeting the UN's Millennium Summit goals, which include halving global poverty and arresting the spread of HIV/AIDS by 2015.
It encouraged governments in poor countries to follow the example of the Asian "tiger" nations, which invested in health and education early in the development process.
"Given a real choice, poor people in developing countries have smaller families than their parents did," the report said.
"This downturn in fertility at the 'micro' level translates within a generation into potential economic growth at the 'macro' level, in the form of a large group of working-age people supporting relatively fewer older and younger dependents."
A study by the National Research Council in the United States in 1986 concluded that, despite its important effect on households, population growth had no impact on overall economic growth.
But the UNFPA report cited new research to argue the effect of declining fertility in Brazil had been equal to an annual increase of 0.7 per cent in per capita gross domestic product.
AFP