Fish Oil–Derived Fatty Acids in Pregnancy and Wheeze and Asthma in Offspring

BackgroundReduced intake of n−3 long-chain polyunsaturated fatty acids (LCPUFAs) may be a contributing factor to the increasing prevalence of wheezing disorders. We assessed the effect of supplementation with n−3 LCPUFAs in pregnant women on the risk of persistent wheeze and asthma in their offspring. MethodsWe randomly assigned 736 pregnant women at 24 weeks of gestation to receive 2.4 g of n−3 LCPUFA (fish oil) or placebo (olive oil) per day. Their children formed the Copenhagen Prospective Studies on Asthma in Childhood2010 (COPSAC2010) cohort and were followed prospectively with extensive clinical phenotyping. Neither the investigators nor the participants were aware of group assignments during follow-up for the first 3 years of the children’s lives, after which there was a 2-year follow-up period during which only the investigators were unaware of group assignments. The primary end point was persistent wheeze or asthma, and the secondary end points included lower respiratory tract infections, asthma ...