Human chorionic trophoblasts, decidual cells, and macrophages: a histochemical and electron microscopic study.

Human chorion, amnion, and adherent decidua were studied in term placentas obtained at spontaneous normal delivery and at cesarean section from women not in labor. There were no differences in morphologic features or in distribution of acid phosphatase reaction product in the two delivery groups--in trophoblasts, decidual cells, or macrophages of the decidual layer. No diffusion of acid phosphatase reaction product from lysosomes was evident. The significance of these findings is discussed in the context of current hypotheses concerning cellular event associated with labor.