Gestational age is more important for short‐term neonatal outcome than microbial invasion of the amniotic cavity or intra‐amniotic inflammation in preterm prelabor rupture of membranes

The aim of this study was to evaluate, in women with preterm prelabor rupture of membranes ( PPROM ), the impact on short‐term neonatal outcome of microbial invasion of the amniotic cavity ( MIAC ), intra‐amniotic inflammation ( IAI ), and the microorganisms isolated in women with MIAC , when gestational age is taken into account. Material and methods Prospective cohort study. We included women with PPROM (22.0–34.0 weeks of gestation) with available information about MIAC , IAI and short‐term neonatal outcome. MIAC was defined as positive aerobic/anaerobic/genital Mycoplasma culture in amniotic fluid. Definition of IAI was based on interleukin‐6 levels in amniotic fluid. Main outcome measures were Apgar score <7 at 5 min, umbilical artery pH ≤7.0, days in the neonatal intensive care unit, and composite neonatal morbidity, including any of the following: intraventricular hemorrhage grade III – IV , respiratory distress syndrome, early‐onset neonatal sepsis, periventricular leukomalacia, necrotizing enterocolitis, and fetal or neonatal death. Labor was induced after 32.0 weeks if lung maturity was confirmed; and otherwise after 34.0 weeks. Results MIAC and IAI were found in 38% (72/190) and 67% (111/165), respectively. After adjustment for gestational age at delivery, no differences in short‐term neonatal outcome were found between women with either MIAC or IAI , compared with the non‐infection/non‐inflammation (“No‐ MIAC /No‐ IAI ”) group. Furthermore, short‐term neonatal outcome did not differ between the MIAC caused by Ureaplasma spp. group, the MIAC caused by other microorganisms group and the “No‐ MIAC /No‐ IAI ” group. Conclusions Gestational age at delivery seems to be more important for short‐term neonatal outcome than MIAC or IAI in PPROM .