More U.S. women died around the time of childbirth last year, reversing two years of decline, according to provisional data posted Wednesday.

The Centers for Disease Control and Prevention said 688 people died last year during pregnancy or shortly after giving birth. That’s up from 669 deaths in 2023, but down from 2022 and 2021, when it was the highest level in more than 50 years.

The maternal mortality rate rose to 19 deaths per 100,000 live births, up from 18.6 the year before.

The CDC counts women who die while pregnant, during childbirth and up to 42 days after birth from conditions related to pregnancy. Excessive bleeding, blood vessel blockages and infections are leading causes.

Such deaths spiked during the COVID-19 pandemic, as the coronavirus was particularly dangerous to pregnant women. And, in the worst days of the pandemic, burned out physicians may have added to the risk by ignoring pregnant women’s worries, experts say.

The waning of COVID-19 is considered a major reason for the declines in maternal deaths in 2022 and 2023, experts say.

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But those improvements are now being offset by other factors that may reduce access to medical care, experts say. They say the list includes the closure of rural hospitals and the U.S. Supreme Court decision that did away with the federally established right to abortion, which caused some doctors to feel constrained about providing care during pregnancy-related medical emergencies.

The U.S. has one of the highest maternal mortality rate among wealthy nations. Past research has found wide racial disparities in such deaths, with Black women dying at a far higher rate than white women.