Ultrasound evaluation of amniotic fluid: outcome of pregnancies with severe oligohydramnios

We studied a group of 247 patients out of 7725 patients who had an ultrasonic examination between 32 and 36 weeks gestation and were found to have oligohydramnios (amniotic fluid volume (AFV) ⩽ 2.0 cm). We compared the features of labor and mode of delivery and perinatal outcome in this group with that of a normal control group of 247 patients who also had an ultrasonic examination between 32 and 36 weeks gestation and were found to have normal AFV (> 2.0 to < 8.0 cm). The incidence of induction of labor, of elective cesarean section, of pre-term delivery (< 37 weeks' gestation) was significantly higher in the oligohydramnios group (study group) as compared with the incidence in the control group (P < 0.05). The incidence of fetal distress in antenatal and intrapartum period, pH (⩽ 7.2), of low Apgar score (0–5), of intrauterine growth retardation (IUGR) (< tenth centile) infants, of major fetal anomaly and perinatal mortality rate (PNMR) are significantly higher in the oligohydramnios group as compared with the incidence and PNMR in the normal control group (P < 0.05). The ultrasonic finding of oligohydramnios should alert the clinician regarding the possibility of problems in labor and perinatal period.