Rate of stroke increasing among women during, soon after pregnancy

Aug 09, 2011

The stroke rate for pregnant women and those who recently gave birth increased alarmingly over the past dozen years, according to research reported in Stroke: Journal of the American Heart Association.

Researchers gathered data from a large national database of 5 to 8 million discharges from 1000 hospitals and compared the rates of strokes from 1994-1995 to 2006-2007 in women who were pregnant, delivering a baby, and who had recently had a baby.

Pregnancy-related stroke hospitalizations increased 54%, from 4085 in 1994-1995 to 6293 in 2006-2007.

“I am surprised at the magnitude of the increase, which is substantial,” said Elena V Kuklina MD PhD, lead author of the study and senior service fellow and epidemiologist at the Centers for Disease Control and Prevention’s Division for Heart Disease and Stroke Prevention in Atlanta, Georgia. “Our results indicate an urgent need to take a closer look. Stroke is such a debilitating condition. We need to put more effort into prevention.

“When you’re relatively healthy, your stroke risk is not that high,” Kuklina said. “Now more and more women entering pregnancy already have some type of risk factor for stroke, such as obesity, chronic hypertension, diabetes, or congenital heart disease. Since pregnancy by itself is a risk factor, if you have 1 of these other stroke risk factors, it doubles the risk.”

For expectant mothers, the rate of stroke hospitalizations rose 47%. In pregnant women and in women who had a baby in the last 12 weeks (postpartum period), the stroke rate rose 83%. However, the rate remained the same for stroke hospitalizations that occurred during the time immediately surrounding childbirth.

Furthermore, high blood pressure was more prevalent in pregnant women who were hospitalized because of stroke.

In 1994-1995, among pregnant women with stroke, researchers found high blood pressure in:
• 11.3%of the pregnant women prior to birth;
• 23.4% of those at or near delivery; and
• 27.8% of those within 12 weeks of delivery.

In 2006-07, they discovered high blood pressure among stroke patients in:
• 17% of those pregnant;
• 28.5% of those at or near delivery; and
• 40.9% of women in the postpartum period.

It’s best for women to enter pregnancy with ideal cardiovascular health—without additional risk factors, Kuklina said. Next, she suggests developing a comprehensive, multidisciplinary plan that gives doctors and patients guidelines for appropriate monitoring and care before, during, and after childbirth.

A major problem is that pregnant women typically aren’t included in clinical trials because most drugs pose potential harm to the fetus. Therefore, doctors don’t have enough guidance on which medications are best for pregnant women who have an increased risk for stroke.

“We need to do more research on pregnant women specifically,” said Kuklina, who found only 11 cases of pregnancy-related stroke in her review of previously published literature.

The study received no outside funding.

Source: News Release
American Heart Association
July 28, 2011