Relationship of uteroplacental blood flow to placental clearance of maternal plasma C-19 steroids: evaluation of mathematical models.

The concept that the placental clearance of maternal plasma dehydroepiandrosterone sulfate through estradiol formation is a function of uteroplacental blood flow in women has been disputed. We obtained data on the clearance of maternal plasma dehydroepiandrosterone through placental estradiol formation in the baboon and used these data to evaluate some mathematical models of placental clearance. Our evaluation shows that the placental clearance of dehydroepiandrosterone is proportional to uteroplacental blood flow in the baboon.