Clot-busting drugs, such as rt-PA or urokinase, can be used to treat strokes during pregnancy, but there are important risks for the mother and fetus, according to a new report.

The safety and effectiveness of these drugs to treat strokes during pregnancy had not been well studied, due in large part to the rarity of the problem. In a previous study, “the rate of stroke during pregnancy was estimated at 32 per 100,000 deliveries,” senior author Dr. Steven R. Levine, from the Mount Sinai School of Medicine in New York, told Reuters Health.

The report, appearing in the journal Neurology, describes eight pregnant women who were treated with clot busters, also known as “thrombolytic” drugs, for stroke.

Our study, which involved a national survey of our colleagues, is not comprehensive, but it “shows that you can treat most pregnant stroke patients safely with thrombolytic therapy,” Levine said.

The women ranged in age from 21 to 43 years and nearly all were in the first trimester of pregnancy when the stroke occurred. Four of the patients were treated with rt-PA and four patients received urokinase.

One woman died when her doctors tried to open a blocked blood vessel with a tiny catheter, while the others experienced no major complications.

Among the seven surviving women, three underwent therapeutic abortions, two had miscarriages, and two had healthy deliveries, the report indicates.

“The results suggest that thrombolysis can be performed with good outcomes for the mother and, occasionally, with good outcomes for the baby as well,” Levine noted. Ultimately, “you have to weigh the risks of the stroke against the risks of the treatment.”

SOURCE: Neurology, March 14, 2006.