Correlation of residual amniotic fluid and perinatal outcomes in periviable preterm premature rupture of membranes.

Objective: To correlate maternal and fetal outcomes of pregnancies affected by preterm premature rupture of membranes (PPROM) at < 24 weeks' gestational age with the amount of residual amniotic fluid as determined by sonographic evaluation.

Methods: We searched the local maternal-fetal medicine database for the records of all women with PPROM prior to 24 completed weeks of pregnancy. The quantity of residual amniotic fluid determined by ultrasound was recorded and women were separated into two groups: (A) deepest vertical pocket (DVP) ≥ 1 cm, or (B) DVP < 1 cm (severe oligohydramnios). Hospital chart review was undertaken to determine latency to delivery, perinatal death, and maternal complications. Data were analyzed using Fisher exact and Wilcoxon-Mann-Whitney U tests.

Results: We identified 31 subjects, of whom nine elected termination of pregnancy (6 in group A, 3 in group B). Six of 10 subjects in group A had a live delivery without neonatal death, whereas only one of 12 subjects in group B had a live delivery (P = 0.020). Additional complications included placental abruption in 63% in group A and 45% in group B, chorioamnionitis in 50% and 70%, respectively, and postpartum endometritis in 0% and 9%, respectively. None of these differences were statistically significant. There were no cases of maternal sepsis or maternal death in either group. Group A was associated with a later GA at delivery (27.5 weeks vs. 23 weeks, P = 0.07), with the GA at rupture of the membranes similar for both groups.

Conclusion: These results indicate that a higher level of residual amniotic fluid after periviable PPROM is associated with fetal survival and increased latency to delivery without an increase in maternal complications. This information will be valuable in counselling pregnant women with PPROM < 24 weeks.