OBJECTIVE:

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.

STUDY DESIGN:

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

RESULTS:

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.

CONCLUSION:

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.