Women who receive aspirin or other antiplatelet drugs during pregnancy are at lower risk of pre-eclampsia, conclude authors of a study published early Online and in an upcoming edition of The Lancet. But an accompanying comment says that potential risks of aspirin use must be considered by individual mothers before embarking on treatment.
Pre-eclampsia is a multisystem disorder of pregnancy that is usually associated with high blood pressure and proteinuria (excess of serum proteins in the urine).
Dr Lisa Askie, University of Sydney, Australia, with funding from the Australian National Health and Medical Research Council, along with colleagues from Australia and the UK, formed the Perinatal Antiplatelet Review of International Studies (PARIS) collaborative group and did a meta-analysis (a study which combines the results of previous trials) on more than 32,000 women and their babies.
They found that the risks of developing pre-eclampsia, of delivering before 34 weeks and of having a pregnancy with a severe adverse outcome all fell by 10% in those women taking aspirin or other antiplatelet drugs.
Aspirin was found to have no significant effect on the risk of death of the fetus or baby, having a small for gestational age infant, or bleeding events for either the women or their babies. No particular subgroup of women was substantially more or less likely to benefit from aspirin than any other.
The cause of pre-eclampsia remains unclear, although it is known that complications in the maternal spiral arteries in early pregnancy can lead to irregular blood flow to the placenta, causing blood clots in and death to placental tissue. This can lead to activation of the platelets and clotting system and an imbalance between hormones which promote and slow blood flow. Antiplatelet agents such as aspirin are thought to prevent pre-eclampsia by redressing this balance.