Last year, 303,000 women around the world died from pregnancy and birth-related complications. A disproportionate number of these deaths were in developing countries.

“A woman in sub-Saharan Africa is 100 times more likely to die in pregnancy or childbirth than a woman from an industrialized nation,” says Lothar Mikulla, maternal health communications specialist at the United Nations Population Fund (UNFPA). “This is one of the most glaring differences between rich and poor countries.”

Maternal mortality is highest in countries where residents can’t get to or can’t afford adequate health care. To address this problem, UNFPA supports the development of emergency services and trains midwives. Between 2009 and 2014, the organization trained over 66,000 women to assist with childbirth.

“In all countries that have achieved dramatic improvements in maternal death,” says Mikulla, “professionally trained midwives and others with midwifery skills have been a key to success.”

And there have been successes: the maternal death ratio—the ratio of maternal deaths to live births—fell 44 percent between 1990 and 2015. And while taking the photos in this gallery over a period of years, Lynsey Addario says that she noticed this drop. The efforts of organizations like UNFPA and Every Mother Counts may drop the ratio further in the next 25 years.

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