Olympic sprinter Tori Bowie died of complications during childbirth at age 32, according to her autopsy, which was released this week. She was eight months pregnant at the time of her death.

Respiratory distress and eclampsia were listed as potential complications, according to The New York Times .

Bowies death underscores the severity of the maternal mortality problem in the United States, which has a maternal mortality rate that is double if not more than other developed countries like France, Germany, the United Kingdom and Sweden. Her death also underscores the severity of the Black maternal mortality crisis in this country. Black women are three times more likely than white women to die from pregnancy-related causes, according to the Centers for Disease Control and Prevention .

The World Health Organization reports that among the causes of maternal death are severe bleeding after childbirth, infections after childbirth and preeclampsia and eclampsia, or high blood pressure during pregnancy.

And while you may be unfamiliar with eclampsia, you may be aware of preeclampsia and the two are related. Eclampsia is a rare but serious complication of preeclampsia, according to the Cleveland Clinic website .

So, what is eclampsia (and preeclampsia) and what are the signs? Heres what to know.

What is eclampsia?

Eclampsia is when seizures occur when someone is pregnant or after they give birth. It is usually a severe outcome of preeclampsia, which is a pregnancy complication in which someone has high blood pressure and excess protein in their urine, said Dr. Alison Cowan , an OB-GYN in Colorado and head of medical affairs at Mirvie , a health technology company that is working to develop blood tests to determine ones pregnancy risks.

Eclampsia can also develop if a pregnant person has HELLP syndrome (which stands for Hemolysis, Elevated Liver enzymes, Low Platelets) or gestational hypertension, said Dr. Ahizechukwu Eke , director of research in the division of maternal fetal medicine at Johns Hopkins University School of Medicine in Baltimore. But preeclampsia is the most common reason why eclampsia develops.

According to the March of Dimes , preeclampsia occurs in 5% to 8% of pregnancies. Eke said severe preeclampsia occurs in .6% to 1.2% of pregnancies in Western countries, and eclampsia occurs in 2% to 3% of people with severe preeclampsia.

While eclampsia overall is not common, it is serious. Its also considered a new occurrence, meaning the person who suffers from it usually does not have a history of seizures, according to Eke.