Second-trimester polyhydramnios: evaluation with US.

The sonograms of 40 patients with second-trimester polyhydramnios were reviewed to determine (a) whether fetal and maternal conditions occur as often during second-trimester polyhydramnios as during third-trimester polyhydramnios, (b) the frequency of persistence of polyhydramnios into the third trimester, and (c) how sonography can help in maternal and fetal management. Second-trimester polyhydramnios often (62%) persisted into the third trimester. The frequencies of maternal (25%) and fetal (12%) conditions were similar to those previously reported for third-trimester polyhydramnios. Fetal anomalies were always identified on the sonogram that initially demonstrated polyhydramnios. Fetal outcome was excellent in the nondiabetic patient with polyhydramnios in whom no fetal abnormalities were detected on sonograms. In polyhydramnios associated with maternal diabetes mellitus, however, the pregnancy was often (71%) complicated by premature labor or macrosomia. In such patients serial sonographic follow-up is indicated.