Objective: Our purpose was to assess whether antepartum oligohydramnios is associated with adverse perinatal outcomes. Study Design: Women delivered between July 1, 1991, and September 30, 1996, who underwent ultrasonography at ≥34 weeks’ gestation were analyzed. Oligohydramnios was defined as an amniotic fluid index ≤50 mm. Perinatal outcomes in pregnancies with oligohydramnios were compared with those with an amniotic fluid index of >50 mm. Results: In our analysis of 6423 pregnancies, 147 (2.3%) were complicated by oligohydramnios. This complication was associated with increased labor induction (42% vs 18%; P < .001), stillbirth (1.4% vs 0.3%; P < .03), nonreassuring fetal heart rate (48% vs 39%; P < .03), admission to the neonatal intensive care nursery (7% vs 2%; P < .001), meconium aspiration syndrome (1% vs 0.1%; P < .001), and neonatal death (5% vs 0.3%; P < .001). Conclusion: Antepartum oligohydramnios is associated with increased perinatal morbidity and mortality. (Am J Obstet Gynecol 2000;182:909-12.)