title: NSAIDS and risk of miscarriage.
abstract: Gastrointestinal and renal effects are among the most widely studied and recognised adverse effects of non-steroidal anti-inflammatory drugs (NSAIDs), but the objective of this US-based cohort study was to evaluate whether pre-natal NSAID use is associated with increased risk of miscarriage. More than 1,000 pregnant women were recruited and interviewed immediately after positive pregnancy tests. Median gestational age at study entry was 40 days and the main outcome measures were pregnancy outcomes up to 20 weeks of gestation. Fifty three women (5 per cent) reported pre-natal NSAID use around conception or during pregnancy. After adjustment for potential confounders, prenatal NSAID use was associated with an 80 per cent increased risk of miscarriage (95 per cent confidence interval, 1.0 to 3.2). The association was stronger if initial use was around the time of conception or lasted more than a week. Pre-natal aspirin use was similarly associated with increased risk.