Fetal outcome with oligohydramnios in the second trimester.

Thirty-four cases of oligohydramnios in the second trimester were diagnosed by ultrasonography. Nine of these pregnancies were associated with fetal anomalies including Potter syndrome (three), atrioventricular dissociation (two), congenital absence of thyroid (one), and multiple anomalies (three). There were ten unexplained stillbirths, one demise due to abruptio placentae, eight with perinatal morbidity after premature labor or abruptio placentae, and six with live-born term infants. Although oligohydramnios in the second trimester is associated with increased perinatal morbidity, this finding is not associated with a universally poor outcome.