Midtrimester prostaglandin-induced abortion: gross and light microscopic findings in the placenta

A systematic gross and light microscopic study was done of 60 placentas, spontaneously delivered following induction by intra-amniotic PGF2alpha administration. The main findings were: high incidence of marginal and basal decidual hemorrhage, widespread degenerative changes in the decidua and chorionic villi, intervillous congestion and thrombosis and significant underfilling of the fetal vasculature. These changes are discussed in terms of the possible factors underlying the mechanism of prostaglandin-induced abortion.