Aspirin May Cut Pregnancy Complication Risk
Daily use lowers odds for the dangerous spike in blood pressure called preeclampsia
THURSDAY, May 17, 2007 (HealthDay News) -- Women at high risk for the pregnancy complication preeclampsia can lower their odds by 10 percent by taking daily aspirin, a new study suggests.
Preeclampsia is a potentially fatal obstetric complication that can lead to sudden high blood pressure and irregular blood flow. This can activate platelets and the clotting system, which in turn slows blood flow.
The use of aspirin may help counter this effect, according to a report in the May 16 online issue of The Lancet.
"Preeclampsia complicates between about 2 and 8 percent of all pregnancies, and is associated with approximately 10 to 15 percent of the half-million maternal deaths [worldwide] that occur each year," said lead researcher Lisa Askie, a research fellow in the School of Public Health at the University of Sydney, Australia.
Although the benefits of antiplatelet therapy such as daily aspirin are modest, they are important if given to women at risk of preeclampsia, Askie said. "They could potentially result in many thousands less women who experience a bad pregnancy outcome. Hence, particularly for women at high risk of preeclampsia, a more widespread use of antiplatelet agents may be worthwhile," she said.
In the study, Askie and colleagues in the Perinatal Antiplatelet Review of International Studies (PARIS) group looked at the results of 31 preeclampsia prevention trials that included almost 33,000 women and their babies. Women who took aspirin in these trials typically took between 50 milligrams to 150 milligrams of the drug per day.
The researchers found the risks of developing preeclampsia dropped 10 percent among women taking aspirin or other antiplatelet medications. In addition, these women also had a lower risk of delivering before 34 weeks and of having other pregnancy problems.
Moreover, aspirin had no significant effect on the risk of death of the fetus or baby. It didn't boost the risk of bleeding for either mothers or their infants, nor did it raise risks for underweight newborns.
Askie's team said no particular group of women was more or less likely to benefit from aspirin.
"Women at risk of preeclampsia should discuss the potential benefits and harms of this treatment with their doctor," Askie advised.
But one expert was less than impressed with the findings.
"The results of this study were, to a large extent, disappointing," said Dr. James Roberts, the director of the Magee-Womens Research Institute at the University of Pittsburgh, and author of an accompanying editorial.
Roberts had hoped the study would have shown a larger protective effect -- especially in the women who are at the greatest risk for the problem. "It's difficult to determine if it's more beneficial in any subset of women or at what dose," he said.
"In very high-risk women, the use of aspirin is justified," Roberts said. Women who are at the highest risk for preeclampsia are those who have high blood pressure and have also suffered preeclampsia in previous pregnancies. This group "are almost certain to develop it," he said.
Women at risk because of high blood pressure, pre-pregnancy diabetes or preeclampsia in one previous pregnancy have about a 20 percent risk of developing preeclampsia, Roberts noted.
"For these women, you would have to treat 50 with aspirin to prevent one case of preeclampsia," Roberts said. "For a woman, whether benefits outweigh the risks is a decision that she has to work out with her doctor," he said.
To learn more about preeclampsia, visit the U.S. National Library of Medicine.