Pathological studies on the placenta from pre-term and term maternal toxicosis.

Fifty one placentae with maternal pre-term and term toxicosis were studied pathologically. In the severe pre-term maternal toxicosis, the placenta reveals hyperplasia of syncytial cytotrophoblasts(S-cells) with knots, fibrin deposit at their surface, fibrinoid degeneration of the stroma, in addition to marked interstitial fibrosis of chorionic villi. The basement membrane is thick and cytotrophoblasts(C-cells) are scattered beneath it. Decidual arteries are hyalinized, but a few decidual arteries are thick and almost obstructed in their lumina. On the other hand, the placenta of maternal term toxicosis show chorionic villi with few C-cells under the thin S-cell lining. Their basement membrane is thin with well developed vasculosyncytial membrane. Decidual arteries are more hyalinized and widened. These pathological changes seen in term maternal toxicosis are the severer than those of placental aging.