Maternal renal impairment after indomethacin tocolysis.

Indomethacin is widely used to treat both preterm labor and polyhydramnios. Although adverse fetal and neonatal reactions have been described, the use of indomethacin is not thought to pose a risk to the mother. A case of maternal renal function impairment caused by indomethacin therapy for preterm labor at 27 weeks in a twin pregnancy is presented. The patient was given a 17-day course of indomethacin at standard tocolytic doses of 25 mg orally, every 6 hours. She was delivered after a diagnosis of chorioamnionitis was made and antibiotics, including gentamicin, were instituted. Three days post partum the patient was found to have a blood urea nitrogen value of 27 mg/dl and a serum creatinine level of 3.2 mg/dl. Maternal renal function rapidly improved after the discontinuation of gentamicin. This case represents a potentially serious interaction between an aminoglycoside and indomethacin in an otherwise healthy woman at no risk of renal disease. Monitoring of renal function is advisable when potentially nephrotoxic drugs are given with or soon after indomethacin.