Role of placenta in the regulation of fetal erythropoiesis.

We studied erythropoiesis in newborn infants delivered by mothers with normal pregnancy and gestosis. The effects of placental extracts on hemopoiesis in JCR mice were also evaluated. Our results suggest that the placenta is involved in the regulation of fetal erythropoiesis. The placenta activates fetal erythropoiesis during physiological pregnancy, while in pregnant women with gestosis the erythropoiesis-stimulating effect of placentas was less pronounced, which probably determines low reticulocyte content in the umbilical blood.