Histological chorioamnionitis and risk of pulmonary complications in preterm births: a systematic review and Meta-analysis

Histological chorioamnionitis is associated with significant adverse maternal, perinatal and long-term outcome. We performed a meta-analysis of 30 observational studies in order to clarify the association between Histological chorioamnionitis and pulmonary complications, like respiratory distress syndrome and Bronchopulmonary Dysplasia. Unadjusted data extracted from all studies showed that Histological chorioamnionitis has no effect on development of RDS (RR 0.93, 95% CI 1.08-1.67), while it increased the risk of Bronchopulmonary Dysplasia (RR 1.75, 95% CI 1.37-2.23). However, when we restricted the analysis to the studies that adjust for Gestational Age, in order to exclude the influence of prematurity, we found that HCA reduced the risk of respiratory distress syndrome (RR 0.57, CI 95% 0.35-0.93) and it did not affect the development of Bronchopulmonary Dysplasia (RR 0.99, CI 0.76-1.3). Our results confirmed a possible role of prenatal inflammation on lung maturation. However, further prospective studies with a selected population are needed, in order to clarify the role of Histological chorioamnionitis in neonatal pulmonary complications.