June 16, 2003 -- The same aspirin therapy that helps millions reduce their risk of heart attack and stroke may also help pregnant women reduce their risk of preeclampsia, a dangerously high blood pressure condition during pregnancy. A new study shows low-dose aspirin therapy is a safe and inexpensive way to reduce the risk of preeclampsia in at-risk women and help ensure that they deliver a healthy baby.
Preeclampsia is a potentially fatal condition for both mother and baby that usually occurs in the second half of pregnancy. Preeclampsia causes the mother's blood pressure to rise and hampers proper blood flow to the unborn baby, and it can progress to seizures in the mother. If the condition cannot be prevented or brought under control, the only real cure is premature delivery of the fetus, which may not be fully developed.
In a review of 14 recent studies that compared the effectiveness of aspirin therapy vs. placebo in 12,416 pregnant high-risk women, researchers found that aspirin therapy reduced the risk of:
- Premature birth by 21%
- Preeclampsia by 14%
- Spontaneous abortion/miscarriage by 14%
In addition, aspirin therapy also increased the average birth weight of the babies by nearly half a pound. The study did not find any harmful effects.
The results appear in the June issue of Obstetrics and Gynecology.
Researchers say a previous review of research on the issue concluded that aspirin therapy produced only a modest benefit in reducing the risk of preeclampsia and that relatively large numbers of women would have to be treated in order to prevent a single negative outcome.
But researchers argue that the benefit of aspirin therapy shown by this study as well as prior ones would be significantly greater among women known to be at high risk for developing preeclampsia.
Although the cause of preeclampsia is unknown, the following factors are known to increase a woman's risk of developing preeclampsia during pregnancy:
- A history of high blood pressure
- Obesity prior to pregnancy
- Carrying more than one child
- Prior preeclampsia or family history of preeclampsia
- History of diabetes, kidney disease, lupus, or rheumatoid arthritis
"Based on our findings and the established safety of aspirin, it seems reasonable to recommend aspirin therapy to women who are historically at high risk for preeclampsia, particularly those with multiple risk factors," write researcher Aravinthan Coomarasamy, MD, and colleagues at Birmingham Women's Hospital in Birmingham, England.