The world's population is growing at the expense of women's health. With nearly one in five women already mothers by their 18th birthday, the UN has made women's rights the focus of this year's World Population Day.
The world's population grows by roughly 2.6 people per second. In 15 years, the number of people on earth will have increased from 7.3 billion to 8.5 billion, according to the United Nations Population Fund (UNFPA). By 2100, that figure is expected to reach 11.2 billion.
Better living conditions for women and girls could change this trend, which is why "Investing in teenage girls" is the motto of this year's World Population Day. Many aid organizations have also taken on this slogan because they, too, see that improving women's opportunities is one of the keys to preventing overpopulation.
Since proclaiming a World Population Day in 1989, the UN has sought to bring attention problems tied to population growth and to strengthen the rights and health care of mothers.
Education key to curbing pregnancies
"Every year, roughly 74 million women and girls in developing countries experience an unwanted pregnancy primarily because there is a lack of sex education and a lack of contraception. It's also because women and girls aren't given equal rights," said Renate Bähr, the head of the German World Population Foundation (DSW).
That's also why more than 220 million women can't use contraception even though they want to, Bähr added.
Young women in these countries, in particular, have had little access to sex education and contraception up until now, resulting in a large number of teenage pregnancies worldwide. In Niger, for example, there are an estimated 205 births per 1,000 women between the ages of 16 and 19. This rate hasn't changed since 1960. In Somalia, the number of births has risen from 55 to 105 per 1,000 women in this age group.
Family planning a must
Complications during pregnancy and labor are the second leading cause of death among women between the ages of 15 and 19.
"Young girls haven't developed enough physically to carry out a pregnancy to term without complications," DSW's Leonie Müssig says.
The latest figures from the United Nations (UN) shows that small differences between the average number of children per woman can have a considerable impact on the world's population growth. Assuming that the current average of 2.5 children per woman remained the same through the end of the century, the world's population would increase by 26 billion people by 2100.
But using a more moderate calculation, the UN assumes that the international birth rate will sink to two children per women over the next 85 years, meaning that the world's population would increase to only 11.2 billion people. Statistically speaking, another half a child less would mean a world population 7.3 billion by 2100.
More money for girls
Given these calculations, development experts consider investments in education a top priority.
"Educated women and girls would be able to realize their rights to self-determination and voluntary family planning better," said Müssig. Better opportunities for women in the labor market would also mean a decline in birth rates.
"Plus, if more children survived thanks to better medical care, parents would decide against having more children," she said.
Aid organizations are calling on the German government to give more money to projects that strengthen the health and reproductive rights of women.
"Increasing the German development aid budget for 2017 is a step in the right direction," says Cornelia Füllkrug-Weitzel, president of the German aid organization Bread for the World.
But, according to Füllkrug-Weitzel, the German Ministry for Economic Cooperation and Development's budgetary increase from 7.4 to 8 percent - while promising - is clearly too little.