664: Acute inflammation during ascending intra-uterine infection simultaneously progress in both extra-placental membranes and chorionic plate: evidence of anatomic connection between extra-placental membranes and chorionic plate

Abstract

Extra-placental membranes (EPM) and fetal placental surface, that is, chorionic plate (CP), are continuous, and most processes are likely to be seen in both. However, there is no information about whether acute inflammatory processes simultaneously progress in both EPM and CP during ascending intra-uterine infection (AIUI). The objective of the study is to examine this issue. Study population included 179 singleton early preterm-births due to PTL and preterm-PROM. We examined the frequency of inflammation in sub-chorionic fibrin (SCF) and connective tissue (CT) within CP according to the progression of inflammation in EPM(i.e., inflammation-free chorio-decidua [CD] or inflammation restricted to decidua, inflammation restricted to membrane trophoblast (MT) of chorion, inflammation restricted to CT of chorion, and inflammation in amnion), and the frequency of inflammation in MT of chorion, CT of chorion, and amnion within EPM according to the progression of inflammation in CP(i.e., inflammation-free CP, inflammation restricted to SCF of CP, and inflammation in CT of CP). Acute inflammation in EPM and CP was defined according to the previously reported criteria. 1) Inflammation-free CD or inflammation restricted to decidua, inflammation restricted to MT of chorion, inflammation restricted to CT of chorion, and inflammation in amnion were present in 53%, 17%, 17% and 12% of cases; 2) Inflammation-free CP, inflammation restricted to SCF of CP, and inflammation in CT of CP were present in 75%, 10% and 16% of cases; 3) Inflammation in SCF (Fig.1.a) and CT (Fig.1.b) within CP was more frequent according to the progression of inflammation in EPM; 4) Inflammation in MT of chorion (Fig.2.a), CT of chorion (Fig.2.b) and amnion (Fig.2.c) within EPM more developed according to the progression of inflammation in CP. Inflammation in SCF and CT within CP is more frequent according to the progression of inflammation in EPM, and inflammation in MT of chorion, CT of chorion, and amnion within EPM more develops according to the progression of inflammation in CP. This finding suggests that acute inflammatory processes simultaneously progress in both EPM and CP during AIUI.View Large Image Figure ViewerDownload Hi-res image Download (PPT)