898: Placental fetal side thickness correlates with fetal brain injury

Abstract

Exposure to intrauterine inflammation (IUI) has been associated with adverse perinatal sequelae. However, little data exist on utilizing placenta to prognosticate fetal injury in this scenario, especially about correlation of placental thickness vs fetal outcomes. We hypothesized that in the setting of IUI the extent of structural changes of placenta can predict the level of adverse fetal outcomes. At embryonic day (E) 17, CD1 pregnant dams underwent laparotomies and received intrauterine injections of lipopolysaccharide (LPS; a model of IUI) or phosphate-buffered saline (PBS). Placenta and fetal brain were harvested 6 hours after the surgery. Immunohistochemistry was performed to detect microglial activation (ionized calcium-binding adaptor molecule 1, Iba1). Placental thickness and Iba1 expression were measured using Image J. Placental thickness was correlated with microglial activation (Iba1 expression) using the Pearson correlation analysis (Graphpad Prism). Statistically significant (Graphpad Prism) differences were recognized as p< 0.05. Microglial activation was significantly higher in fetal brain exposed to maternal inflammation (MI). Fetal side placental thickness was negatively correlated to the percentage of microglial activation (p< 0.05, r = -0.6245, Pearson correlation analysis). The expression of Iba-1 in fetal brain was significantly associated with placental fetal side thickness. Placental fetal side thickness changes can be considered as a marker to establish the extent of fetal adverse outcomes exposed to MI.