Sen. Elizabeth Warren (D-Mass.) called out the problem of the disproportionately high rate of maternal mortality for black women in the United States and laid out a plan to address it Wednesday at a Houston forum for presidential candidates.

“Measure the values that a country has by how it treats its mamas and its babies. And the United States… has profoundly failed on this front,” Warren said at the forum, organized by She the People, a national network of women of color in politics. “We have failed our mamas; we have failed our babies.”

The U.S. has the worst maternal mortality rate among all developed countries, and though the rate has been falling in other nations, it has been rising in the U.S. in recent years.

Warren called out the “specific problem” facing women of color: The risk of pregnancy-related deaths forblack women is three to four times higher than for white women, according to the U.S. Centers for Disease Control and Prevention.

Tennis star Serena Williams and singer Beyoncé, in her recently released Netflix documentary “Homecoming,” have publicly discussed the difficulties and complications they faced in childbirth.

“The best studies that I’ve seen put it down to just one thing: prejudice,” Warren said Wednesday. “Doctors and nurses don’t hear African American women’s medical issues the same way as they hear the same things from white women.”

“I got a plan,” she added, to cheers from the crowd of about 1,700 people, largely women of color, at the event at Texas Southern University, a historically black college.

“I want to talk to the hospitals... in the language they understand: money.”

Warren laid out a plan to have medical providers’ funding be contingent on the quality of care they give to mothers, and specifically to black moms.

“The hospitals are just going to get a lump of money, and if they bring down those maternal mortality rates, then they get a bonus, and if they don’t, then they’re going to have money taken away from them,” Warren said. “We’ve got to have change, and we’ve got to have change now.”