Shakima Tozay was 37 years old and six months pregnant when a nurse, checking the fetal heart rate of the baby boy she was carrying, referred to him as “a hoodlum.” Ms. Tozay, a social worker, froze. She had just been hospitalized at Providence Regional Medical Center in Everett, Wash., with pre-eclampsia, a life-threatening complication of pregnancy, and she is Black.

“A ‘hoodlum’?” she said. “Why would you call him that?”

The fetus was 14 inches long and weighed little more than a box of chocolates.

A doctor who came into the room downplayed the comment, saying the nurse was just kidding, but that only hurt Ms. Tozay more. She was already distressed: She and her husband lost an earlier twin pregnancy, and now she worried this baby was at risk, too. The hospital later apologized for the nurse’s behavior, but the damage was done.

Black women, who die of pregnancy-related complications at two to three times the rate of white women, say that remarks like these, often made when they are most vulnerable, reflect pervasive bias in the medical system. They report that medical staff don’t listen to them when they complain of symptoms, and dismiss or downplay their concerns. Studies validate their experiences: Analyses of taped conversations between physicians and patients have found that doctors dominate the conversation more with Black patients and don’t ask as many questions as they do of white patients. In medical notes, doctors are more likely to express skepticism about the symptoms Black patients report.

Hovering over these experiences is the stark reality that Black women have worse pregnancy outcomes, lose more infants in the first year of life and have higher rates of preterm birth and stillbirth, when compared with white women. Glaring racial disparities in health outcomes persist between white women and even the wealthiest Black women, and between Black women and white women who experience the same complications.

These findings have forced the medical establishment to acknowledge and confront its biases. Many health systems have mandated anti-bias training for faculty. Some hospital committees that review cases with poor outcomes in order to identify the causes now consider whether racial bias played a role.