To examine the correlation between antenatal exposure to NSAIDs and the risk for PPHN, Linda J. Van Marter, M.D., M.P.H., from Boston Children's Hospital, and colleagues interviewed 377 women whose infants had PPHN, along with 836 control mother/infant pairs matched by hospital and delivery date. Questions included information about prescribed and over-the-counter medications used during pregnancy.The researchers found that 8.8 percent of infants with PPHN were exposed to any NSAID during the third trimester, compared with 9.6 percent of controls (odds ratio, 0.8; 95 percent confidence interval, 0.5 to 1.3). The odds of PPHN were elevated for infants whose mothers consumed aspirin during the third trimester, but the lower 95 percent confidence interval included the null. Neither ibuprofen use during the third trimester nor non-aspirin NSAIDs at any time during pregnancy was associated with an increased risk of PPHN. There was also no association found between third-trimester acetaminophen exposure and the occurrence of PPHN.