The Fetoplacental Circulation During Parturition: Evidence From Residual Placental Blood Volume
The volume of blood left in the fetal part of the placenta after early clamping of the umbilical cord (residual placental blood) was measured in 24 deliveries, and found to be larger among infants born by the vaginal route compared to those born by cesarean section. The result is interpreted as an evidence of a temporary depositing of blood in the placenta during the second stage of labor. As early clamping of the umbilical cord, therefore, among cases of vaginal deliveries, amounts to a blood-letting of about 30 ml of the newborn infant's own blood, it is considered not to be a physiological procedure. The investigation has also demonstrated that the residual placental blood, among cases of vaginally delivered and early clamped infants, fails to represent the intrauterine distribution of the fetoplacental blood volume. Finally, the investigation shows that the placental transfusion, which takes place in late clamped infants, partly originates from previously deposited fetal blood, partly from placental blood. See table in the PDF file. See image in the PDF file. See image in the PDF file.