Childhood asthma and use during pregnancy of acetaminophen. A critical review.

The possible association between acetaminophen use during pregnancy and childhood asthma has been a subject of interest based on the theory that acetaminophen metabolism may deplete glutathione in the developing lung, leading to oxidative damage and inflammation. Epidemiology studies from eight centers have reported conflicting results. In some cases, end points of these studies have included wheezing in very young children, which is a poor predictor of asthma. Other study problems have included the common use of acetaminophen as the analgesic and antipyretic of choice during pregnancy. Because acetaminophen use may be a marker for infectious or inflammatory disorders, the results of the epidemiology studies may be influenced by confounding by indication. A placebo-controlled randomized trial of acetaminophen use during pregnancy would be helpful in resolving the question of whether acetaminophen use causes childhood asthma. At present, the evidence is inconclusive that any such association is causal.