Persistent pulmonary hypertension in a premature newborn after 16 hours of antenatal indomethacin exposure.

Premature constriction of the fetal ductus arteriosus has been described with long-term indomethacin therapy, but not in fetuses who have been exposed to the drug for less than 72 hours. The sensitivity of the ductus to extended indomethacin tocolysis increases with advancing gestational age. For this reason, it is recommended that indomethacin not be used beyond 31 weeks of gestation. In the present case the gestational age of the patient was 27 weeks and the period of indomethacin exposure was only 16 hours. Our observations of pulmonary hypertension in this case suggest that administration of indomethacin even hours before delivery can significantly affect the ductus arteriosus and the pulmonary vasculature.