Prelabor rupture of membranes between 34 and 37 weeks: the intraamniotic inflammatory response and neonatal outcomes

Abstract

Objective: We sought to determine the influence of microbial invasion of the amniotic cavity (MIAC) and acute histologic chorioamnionitis (HCA) on the intensity of the intraamniotic inflammatory response and neonatal morbidity in preterm prelabor rupture of membranes (PPROM) between 34-37 weeks.

Study design: This study included 99 women with singleton pregnancies complicated by PPROM between the gestational ages of 34-37 weeks. Amniocenteses were performed at the time of admission, and MIAC and amniotic fluid interleukin-6 concentrations were determined. After delivery, the placenta was evaluated for the presence of HCA.

Results: Women with both MIAC and HCA had the highest intraamniotic inflammatory response, which was mediated by interleukin-6 concentrations (both MIAC and HCA: median 2164.0 pg/mL; HCA alone: median 654.8 pg/mL; MIAC alone: median 784.1 pg/mL; neither MIAC nor HCA: median 383.0 pg/mL; P < .0001) and the highest incidence of newborns with early-onset sepsis (P = .02).

Conclusion: Both MIAC and HCA affect the intensity of the intraamniotic inflammatory response and the incidence of early-onset sepsis following PPROM between 34-37 weeks. The intensity of the intraamniotic inflammatory response should be considered in the clinical management of PPROM between 34-37 weeks.

Keywords: amniotic fluid; gestational age; histologic chorioamnionitis; interleukin-6; microbial invasion of the amniotic cavity.