Chorioamnionitis and fetal response in stillbirth

The purpose of this study was to determine the incidence of chorioamnionitis and fetal inflammatory response in a stillborn cohort and the relationship of fetal response to spontaneous labor, unexplained antepartum death, and spontaneous preterm death.

In a 15-year hospital cohort study, placental histopathologic evidence, labor onset, gestation, and cause of death classification data were analyzed.

Of 459 stillbirths, 428 stillbirths were included. The incidence of chorioamnionitis was 36.9%, with higher rates evident in early and late gestation. A fetal inflammatory response was present in 13.3% and correlated with spontaneous labor and very early spontaneous preterm death. The absence of a fetal response was associated with unexplained antepartum death.

The increased incidence of chorioamnionitis at extremes of gestation in stillbirth is novel and has important implications. The impact of a fetal response is gestation dependent and its absence is associated with unexplained antepartum death.