Estimation of Water Transfer from Amniotic Fluid to Fetus. ∗

Abstract

Summary

Deuterium oxide was injected into the amniotic sac of pregnant women one hour or less before delivery by Cesarean section. The tracer concentration in cord blood invariably exceeded the calculated equilibrium value. This observation led to the conclusion that time activity curves for the fetal compartment must pass through a maximum. On the basis of experiments with hy-drodynamic models this was interpreted to mean that at least 25%, probably more than 50% of the water transfer from the amniotic fluid to mother is accomplished through the intermedium of the fetus.