A study of the placenta in pregnancy treated by stilbestrol

Abstract

A statistical investigation has been made of effects of stilbestrol therapy in pregnancy upon weights of baby and placenta. Changes in gross and microscopic placental structure due to stilbestrol have also been sought. Stilbestrol-treated and untreated control groups of primiparous full-term and premature births, as well as cases with toxemia of pregnancy, have been included.Evidence is presented that weights of both baby and placenta are increased in stilbestrol-treated full-term and premature births and in the toxemia group. Ratios of baby weight to placental weight were the same for stilbestrol and control groups in the full-term and toxemia cases, and were decreased in the stilbestrol-treated premature birth group. Stilbestrol stimulates increase in weight and presumably size of both infant and placenta. One by-product of placental overgrowth found is an increased proportion of circummarginate placentas in all three stilbestrol groups, as compared to controls.Gross and microscopic study indicated more frequent occurrence of marked placental calcification and intervillous thrombosis in full-term stilbestrol-treated placentas. In premature stilbestrol-treated cases there was similarly a higher incidence of mature chorionic villi and intervillous thrombi. No nontoxic premature separations were encountered after stilbestrol therapy. The toxemia cases with stilbestrol therapy more frequently had thrombosis of decidual sinusoids and intervillous thrombi than controls, but the number of such cases was small. No specific histologic change was observed which was attributable to stilbestrol treatment.