NSAID Use During Pregnancy May Double Miscarriage Risk

Women taking nonaspirin nonsteroidal anti-inflammatory drugs (NSAIDs) during early pregnancy may face more than double the risk for spontaneous abortion, a recent study showed (Nakhai-Pour HR, et al. CMAJ. 2011 Sept 6. Epub ahead of print). This risk was associated with all NSAIDs studied, although at varying levels, suggesting a class effect. In addition, the risk was not dose-dependent.

The researchers enrolled 4705 women who had experienced spontaneous abortion, along with 47,050 controls matched according to date of the spontaneous abortion and gestational age. Of the women who had spontaneous abortions, 352 (7.5%) had filled 1 or more nonaspirin NSAID prescriptions during their pregnancies. Among women who did not have spontaneous abortions, 1213 (2.6%) had filled prescriptions for nonaspirin NSAIDs during pregnancy.

Naproxen was used with the most prevalence among all the women— 2.8% among women who experienced spontaneous abortion and 0.9% among those who did not. The next most often used nonaspirin NSAID was ibuprofen— used by 1.3% of women with spontaneous abortions and 0.6% of those without—followed by rofecoxib (0.8% vs 0.3%, respectively), diclofenac (0.7% vs 0.2%, respectively), and celecoxib (0.6% vs 0.2%, respectively.) Use of 2 or more nonaspirin NSAIDs during pregnancy was reported in 0.6% of women with spontaneous abortions and in 0.2% of the control group.

After adjustment for potential confounders, results showed a 2.4-fold increase in the risk for spontaneous abortion in women who used any type of nonaspirin NSAID during pregnancy. Although all nonaspirin NSAIDs imparted this risk, it was found to be highest among women who used diclofenac alone and lowest in women who used rofecoxib alone