More American women are dying in childbirth, and one group is affected disproportionately.

Why are American women dying in childbirth at higher rates than they were in 1987? On Friday, the Economist published a comprehensive report on the dilemma and found that women in the United States are three times more likely to die of complications relating to childbirth than women in other developed countries like Germany, Japan and Britain and Czech Republic.

And black women in the United States are disproportionately impacted by pregnancy-related deaths. According to the Centers for Disease Control, black women experienced 42.8 deaths per 100,000 live births in 2011, compared with 12.5 deaths per 100,000 live births of their white counterparts. A report by the Center for Reproductive Rights calculated that black women died in childbirth three to four times more often than their white counterparts over between 1990 and 2013.

A report in The Washington Post found that black women in Mississippi were particularly affected by this problem. Black women accounted for 55 percent of pregnancy-related deaths there, compared to about 29 percent for white women. Mississippi has the biggest black population in the country.

A study conducted at the University of Alabama hospital in Birmingham, Alabama, found that black women at the hospital were not dying in childbirth at rates consistent with the national average. The city’s black population is 73 percent, compared with 13 percent nationally. Researchers, who studied two decades of records, have theories about why their hospital had lower rates of death among black women. The abundance of resources at a university medical center was one.

Another considered was geographic location. “Maybe it matters in rural areas, in these rural medical centers, that you are African-American or Caucasian,”  said the lead author of the study, Dr. Michael Froelich to Al.com. “Maybe there are barriers. And it could be that some people seek medical care later.”

Georgia has the highest maternal mortality rate, according to RH Reality check, a website that covers women’s reproductive health issues. The maternal mortality rate for white women in Georgia between 2010-2012 was 14 per 100,000 live births. For black women, it was 49 per 100,000.

Why is this happening to black women specifically? High rates of poverty and obesity and limited access to health care are two reasons the Economist gives. Also, diabetes and heart disease are risks more likely to affect black women, says a report by the Center for Reproductive Rights. However, the Centers for Disease Control says the reasons for overall increase in maternal mortality aren’t entirely clear.

According to the Economist, 18.5 of every 100,000 live births in the U.S. ends in death. In 2013, America was one of only 8 countries where the rate of childbirth death increased, according to National Institutes of Health. The others? Afghanistan, Greece, South Sudan,  El Salvador, South Sudan and the tiny statelets of Belize, Guinea-Bissau and Seychelles.

Collier Meyerson is a reporter at Fusion with a focus on race and politics. She lives in Brooklyn.