Between 1998 and 2009, the rate of serious complications like heart attack, stroke, severe bleeding and kidney failure during or after childbirth roughly doubled among U.S. women, according to researchers at the Centers for Disease Control and Prevention (CDC).

In 2008-2009, there were 129 cases of severe complications for every 10,000 women who delivered in a hospital. That was up 75 percent from a decade earlier.

At the same time, complications during women's post-delivery hospital stay also rose: There were 29 cases for every 10,000 women - up 114 percent from 10 years before.

Serious complications and deaths from childbirth are still uncommon in the U.S. Over four million women give birth each year, and this study found about 590,000 cases of severe complications over 11 years.

"We don't want to send the message that pregnant women should be afraid," said Dr. William M. Callaghan of the CDC, who led the study.

With this type of study, which used discharge records from U.S. hospitals, it's not possible to tell why childbirth complications rose, Callaghan said.

But it's "well-documented" from other research that more women are giving birth at older ages, are obese, or have certain health conditions like high blood pressure and diabetes, he added.

There are also more young women with serious conditions, like congenital heart defects, who are surviving and having children.

"The characteristics of the pregnant population are changing," Callaghan said, so it's not unexpected that rates of certain complications might rise.

Another recent CDC study found that minority women are at particular risk. Between 1993 and 2006, minority women accounted for 41 percent of all births nationwide, but 62 percent of all pregnancy-related deaths.

Black women were at greatest risk. For every 100,000 babies born to African Americans, 32 to 35 mothers died. That was roughly four times the rate among white mothers.

Heart problems were the most common cause of death. And in this latest study, Callaghan's team found that one childbirth complication - the need for cardiac surgery during or after delivery - showed a "dramatic" rise over time.

It was still rare: In 2008-2009, just under 5 per 10,000 women needed a heart procedure during delivery, for example. But that was up 75 percent from a decade before.

Callaghan said the bottom line for women is to be as healthy as possible before pregnancy. Losing weight if you are obese, and getting high blood pressure and diabetes under control, are some ways to do that.

If you have existing medical conditions, like heart disease, it's even more important to see your doctor before pregnancy, Callaghan said.

"Not all complications can be avoided, of course," he said. "But the best outcomes happen when a woman is as healthy as possible going into pregnancy."

He added that some women with pre-existing medical conditions may need to see an obstetrician who specializes in high-risk pregnancies.

"Most women do fine," however, Callaghan said. "And even most women with significant disease before pregnancy do fine."

SOURCE: bit.ly/RTTTXJ Obstetrics & Gynecology, November 2012.

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