Placental abruption is associated with histologic evidence of inflammation: The New Jersey-Placental Abruption Study

Abstract

INFLAMMATION: THE NEW JERSEY-PLACENTAL ABRUPTION STUDY CARL NATH, JOHN SMULIAN, SUSAN SHEN-SCHWARZ, LILLIAN KAMINSKY, CANDE ANANTH, University of Medicine and Dentistry of New Jersey, Obstetrics, Gynecology and Reproductive Sciences, New Brunswick, New Jersey, Saint Peter’s University Hospital, New Brunswick, New Jersey OBJECTIVE: Placental abruption has been associated with vascular dysfunction and placental inflammation. Recent studies suggest a strong heterogeneity in the clinical pathways that lead to abruption in preterm and term gestations. We hypothesized that placental abruption is associated with an increased incidence of histologic chorioamnionitis. Our objective was to determine if this association was dependent on the severity of chorioamnionitis. STUDY DESIGN: Data were derived from the New Jersey-Placental Abruption Study, an ongoing, multicenter, case-control study conducted in New Jersey since August 2002. Cases (n=137) were identified based on a clinical or histologic diagnosis of abruption, and controls (n=154) were matched to cases based on parity and maternal race. Histologic evaluation was performed by two perinatal pathologists who were blinded to abruption status. Preterm birth was defined as !37 weeks and placental grading of chorioamnionitis was based on standardized terminology. The association between chorioamnionitis and abruption was quantified based on odds ratio (OR) with 95% confidence interval (CI). RESULTS: The incidence of histologic chorioamnionitis was 31.3% for preterm abruption and 34.2% for term abruption. There was an increased odds of abruption being associated with severe chorioamnionitis. CONCLUSION: Severe histologic chorioamnionitis was associated with abruption. This finding suggests that inflammation plays a significant role in the pathway that leads to abruption both in preterm and term gestations.