Free Estrone, Free Estradiol, Free Estriol, Free Estetrol, Total Estriol and Dehydroepiandrosterone Sulfate in Mother and Fetus at Delivery

To elucidate estrogen related factors in the mother and fetus at the time of expulsion, maternal blood and umbilical arteriovenous blood samples were collected from the same women and F-E_1,F-E_2,F-E_3,F-E_4 and T-E_3 were determined simultaneously by RIA DHA-S, using the acid fluorescence reaction. The 4-fractions of free estrogen in the maternalblood were high in the order of F-E_1>F-E_2>F-E_3>F-E_4,and for umbilical arteriovenous blood, the order was F-E_3>F-E_2>F-E_1>F-E_4. The dehydroepiandrosterone sulfate level, as the precursor of estrogen, was higher in umbilical arteriovenous blood than in maternal peripheral blood, therefore, the dehydroepiandrosterone sulfate is probably excessively secreted in the fetal adrenals. These results suggest that there is a difference in the production pattern and the metabolism in each fraction of these estrogens. The free estetrol in the maternal blood is assumed to be derived from the feto-placental system, considering the production pathway, as the free estetrol level was higher in the umbilical arteriovenous blood than in the maternal blood.