U.S. researchers are reporting a disturbing rise during the past decade in the number of pregnant women suffering from strokes.
They attribute the trend to the fact that more and more women are becoming pregnant with pre-existing medical conditions that put them at an elevated risk of a stroke; some are overweight, diabetic, have high blood pressure or a congenital heart defect. To further complicate matters, many women are postponing their first child and thereby increasing their chances of experiencing a difficult pregnancy.
The findings, published Thursday in the journal Stroke, are based on data from 1,000 American hospitals.
Women treated for pregnancy-related strokes shot up by 54 per cent to about 6,300 cases in 2006-07 from about 4,100 in 1994-95. (Over that time period, the total number of pregnancies remained fairly stable. So the surge in strokes can't be blamed on just more pregnancies.)
"I am surprised at the magnitude of increase, which is substantial," said the study's lead author, Elena Kuklina, an epidemiologist with U.S. Centers for Disease Control and Prevention in Atlanta, Ga.
"Ten years ago, women with certain chronic conditions were not even thinking about becoming pregnant. But now they are … and they don't realize it comes with some risks."
A similar study has not yet been carried out in Canada, but "I think we could definitely extrapolate this data to the Canadian population," said Cheryl Jaigobin, a neurologist at the University Health Network in Toronto.
"Just like in the United States, some pregnant women in Canada are older and have other risk factors for stroke such as hypertension," she noted.
Although worrisome, the study must be kept in perspective, added Dr. Jaigobin. "It's not an epidemic." Only a small fraction of pregnant women suffer strokes - even with the recent increase. The U.S. figures indicate that there were 22 strokes for every 100,000 pregnancies in 2006, up from 12 per 100,000 in 1994.
Nonetheless, more needs to be done to address the growing problem, said Moira Kapral, an associate professor at the University of Toronto. "There are not a lot of studies on the best treatments."