Perinatal outcomes of polyhydramnios without associated congenital fetal anomalies after the gestational age of 20 weeks

Background: Polyhydramnios carries a high rate of complications during pregnancy and adverse perinatal outcomes. We could find no studies of this condition in a large Asian population. The aim of this investigation was to evaluate the risks of adverse perinatal outcomes in a large study population with polyhydramnios without associated fetal anomalies after the gestational age of 20 weeks in Taiwan. Methods: We retrospectively reviewed the computerized records of women who had babies without associated fetal anomalies after the gestational age of 20 weeks at Chang Gung Memorial Hospital from July 1990 to December 2001. Possible confounding factors that could affect the occurrence of polyhydramnios were analyzed. We then investigated the relative risks of these events to adverse perinatal outcome by adjusting the variants. Results: Significantly higher incidences of preeclampsia, placental abruption, placenta accreta, past history of fetal death or preterm delivery, multiple pregnancy, body weight gain ≧ 20kg during pregnancy and primiparity were noted in patients with polyhydramnios than in patients without this condition. The presence of polyhydramnios significantly increased the rate of preterm delivery, low birth weight or very low birth weight, low one- and five-minute Apgar scores, fetal death, large for gestational age babies, meconium-stained amniotic fluid, Cesarean section, fetal distress in labor, NICU transfer and neonatal death. Conclusions: Polyhydramnios carried a higher incidence of adverse perinatal outcomes, such as low Apgar scores, fetal death, fetal distress in labor, NICU transfer and neonatal death, despite exclusion of congenital anomalies from the study population. Detailed antepartum fetal well-being surveillance, intensive intrapartum monitoring and further attention postpartum are warranted in patients with this condition.