ABSTRACT
OBJECTIVE:Ultrasound estimation of amniotic fluid volume (AFI) is a critical component of antenatal surveillance. Alterations in AFI have classically been considered an indication of fetal compromise. Thus, this study was undertaken to determine whether there is any association between idiopathic polyhydramnios or oligohydramnios and adverse perinatal outcome. METHODS:Women delivered between December 1999 and November 2005, and who underwent ultrasonography from 26 to 41 weeks gestation were analyzed. Twenty-seven consecutive women with singleton pregnancies complicated by idiopathic polyhydramnios (amniotic fluid index>25) and 31 women complicated by oligohydraminos (amniotic fluid index<5) were included in this study. We reviewed the perinatal outcomes including preterm delivery, birth weight, primary cesarean section rate and indication, Apgar score (1-min and 5-min), and admission to NICU (neonatal intensive care unit). These findings were compared with those of 50 matched control patients with normal amniotic fluid volume. RESULTS:We observed that idiopathic oligohydramnios was significantly associated with primary perinatal outcome (Cesarean delivery for fetal distress) as well as secondary outcome variables such as birthweight, SGA (small for gestational age), Apgar score<7 at 1-min, 5-min, and NICU admission rates. On the other hand, idiopathic polyhydramnios did not correlate with any other perinatal outcome, except for rates of LGA (large for gestational age). CONCLUSION:The present study suggests that AFI is a weak predictor of perinatal outcome than has been classically suggested. But we demonstrated that the AFI identification of polyhydramnios was helpful in identifying LGA, and idiopathic oligohydramnios was a significant predictor of poor perinatal outcome.