African-American, Native American and Alaska Native women die of pregnancy-related causes at a rate about three times higher than those of white women, the Centers for Disease Control and Prevention reported on Tuesday.

The racial disparity has persisted, even grown, for years despite frequent calls to improve access to medical care for women of color. Sixty percent of all pregnancy-related deaths can be prevented with better health care, communication and support, as well as access to stable housing and transportation, the researchers concluded.

“The bottom line is that too many women are dying largely preventable deaths associated with their pregnancy,” said Dr. Anne Schuchat, principal deputy director of the C.D.C.

“We have the means to identify and close gaps in the care they receive," she added. While not all of the deaths can be prevented, “we can and should do more.”