Borderline oligohydramnios in singleton pregnancies with premature rupture of the amniotic membranes: obstetric management and perinatal outcome

Aim To examine the attitude of the obstetricians and the perinatal outcome of pregnancies complicated by premature rupture of the amniotic membranes (PROM) with associated borderline oligohydramnios. Borderline oligohydramnios was defined as an AFI between 5 and 10. Methods Over 6 months the authors reviewed all singleton pregnancies who were admitted because of PROM in the antenatal ward. Initial assessment of the pregnancy with ultrasound happened shortly after admission. Cases with borderline oligohydramnios were included in the study. The fetal-placental circulation as assessed with umbilical artery Doppler was normal in all cases. Pregnancies with congenital fetal malformations or in labour were excluded. The authors collected data relevant to the mode of delivery and the perinatal outcome. Results 28 cases of PROM and borderline oligohydramnios were identified. 15 women (54%) delivered by Caesarean section. In nine cases this was an elective or semielective procedure. 11 women achieved spontaneous vaginal delivery, two had an operative vaginal delivery. Gestational age at delivery ranged from 24+2 until 38+5. The birth weight ranged from 560 to 3290 g. Apgar score less than 7 at 1 min was noted in four cases. These neonates were admitted to neonatal intensive care unit. There was one neonatal death but no other cases of severe perinatal morbidity. Conclusion The authors conclude that cases of PROM and borderline oligohydramnios are managed aggressively in our unit with high rates of Caesarean section.