Measurement of the villus surface in normal and pathologic placentas

Abstract

The surface of the placental villi in 405 normal and pathologic placentas has been measured by means of a planimetric method. The surface area of a normal and mature placenta varies between 11 and 14 sq. M., with an average of 12.50 sq. M.In case of toxemia, hypermaturity, syphilis, erythroblastosis, and diabetes, the placental surface is decreased. In twin pregnancy it is increased in proportion to the combined weight of the 2 fetuses. The placental surface is also increased in cardiac failures.A significant decrease in the placental surface in cases of inexplicable fetal stress has been found, and it is believed that a kind of fetal stress is due to loss of placental efficiency.The method of measuring the placental surface, although slow and laborious, is of greatest interest in fetal physiology and is bound to be very useful in obstetrics.