Constricting effect of indomethacin on the ductus arteriosus of the fetus is well known. The fetal effects of other nonsteroid anti-inflammatory drugs (NSAIDs) like naproxen are not well reported. We report here a case of a 3,790-g term neonate who developed persistent pulmonary hypertension after birth with a closed ductus arteriosus. The mother admitted to taking naproxen sodium immediately prior to the birth of the infant. The course of illness was progressively better on conservative management. Like indomethacin, other NSAIDs can also cause premature closure of fetal ductus arteriosus, pulmonary hypertension, and life-threatening problems to the neonate. Patient education regarding over-the-counter pain medication during pregnancy should be emphasized.