RESIDUAL AMNIOTIC-FLUID VOLUME IN PRETERM RUPTURE OF MEMBRANES - ASSOCIATION WITH FETAL PRESENTATION AND INCIDENCE OF CLINICAL AND HISTOLOGIC EVIDENCE OF INFECTION

The objective of this study was assess whether residual amniotic fluid volume (AFV) following premature rupture of the membranes (FROM) is a ssociated with fetal presentation, or the prevalence of either clinica l or histologic infection in patients delivering below 32 weeks' gesta tion. From an established database of 465 deliveries below 32 weeks' g estation, patients with singleton, nonanomalous fetuses with AFV asses sment within 24 hours of delivery were studied (n=146). Fetal presenta tion was confirmed by ultrasound identifying 46 breech and 100 vertex- presenting fetuses. Premature rupture of the membranes was diagnosed b y sterile speculum examination. Clinical chorioamnionitis was diagnose d by previously published criteria. Histopathology examination of the extraplacental amnion and the umbilical cord were performed by a singl e pathologist blinded to clinical data. Outcome variables evaluated: r upture-to-delivery interval, gestational age at delivery, neonatal mor bidity parameters (1- and 5-min Apgar scores <5 and 7, respectively; i ncidence of respiratory distress syndrome; bronchopulmonary dysplasia; retinopathy of prematurity; neonatal sepsis; intraventricular hemorrh age; days of ventilation; and hospitalization), and placental histolog ic parameters of maternal and/or fetal acute inflammation. Statistical analysis included contingency tables and analysis of variance with p< .05 considered significant, after corrections for multiple comparisons when appropriate. Residual AF volume following FROM was significantly lower in breech compared with vertex presentation (AFV=0 in 20 vs. 34 ; AFV=1 in 19 vs. 27; AFV=2 in 7 vs. 39, respectively, p=.014). No sig nificant difference was noted in the rupture-to-delivery interval, ges tational age at delivery, neonatal morbidity parameters, or histologic evidence of maternal and/or fetal acute inflammation (50% vs. 42%, p> .2) between gestations with breech or vertex presentations. The incide nce of clinical chorioamnionitis was significantly lower in breech com pared with vertex presention (40% vs. 60%, p<.05). We conclude that fo llowing FROM below 32 weeks' gestation, in breech-presenting fetuses, the residual AFV and incidence of clinical chorioamnionitis are signif icantly decreased compared with vertex-presenting fetuses.