56 Outcome of Neonates Less than 30 Weeks with Histological Chorioamnionitis

To determine the short term outcome of newborns less than 30 weeks gestation when there is definite placental histological chorioamnionitis.

Retrospective analysis of records of all neonates delivered at our institution from Jan 1989 through to Jan 1999. This information was retrieved from our perinatal database and pathology database. The population was stratified according to the presence or absence of histological chorioamnionitis. Statistical analysis was performed using Student's t test and Mann Whitney. Logistic regression was used to control for potential confounding variables.

There were 392 neonates less than 30 weeks delivered during this time period. Complete placental histology was available on 342 patients (87.4%). Histological chorioamnionitis was identified in 140 (40.9%) cases. Those with histological chorioamnionitis delivered sooner (26.3 weeks versus 27.5 weeks), were of lower birth weight (920.1 grams versus 1029.8 grams ) and had lower 5 min apgars.

Neonatal septicaemia and pneumonia were strongly associated with underlying histological chorioamnionitis. Neonatal septicaemia occurred in 10.7% of live births where there was a diagnosis of severe histological chorioamnionitis (versus 1.5% without p<0.05). The organisms most commonly isolated were group B strep, E. coli and Candida albicans. All cases of septicaemia had received antepartum antibiotics. There was a significant reduction in the odds of developing RDS ( OR 0.43, p value 0.001) and odds of dying in the neonatal period (OR 0.38, p value 0.001) when histological chorioamnionitis was present.

Severe histological chorioamnionitis increases the risk of premature delivery and is strongly associated with neonatal sepsis. There is a significant reduction in the incidence of RDS and neonatal mortality in patients with histological chorioamnionitis .