[Study on the clinical evaluation of DHAS loading as a fetoplacental function test--effect of DHAS on estrogen metabolism at a fetoplacental unit].

To evaluate estrogen metabolism in the fetoplacental unit after dehydroepiandrosterone-sulfate (DHAS) injection to the mother, unconjugated estrone, estradiol, estriol and estetrol in maternal vein (MV), umbilical vein (UV), umbilical artery (UA) and amniotic fluid (AF) were measured after DHAS injection. Eighteen normal obstetric patients (37-39W) on whom was performed elective repeat cesarean section were injected with 100 mg of DHAS 30-60 minutes (7 cases), 120 minutes (6 cases), 180-240 minutes (5 cases) before delivery. The injection of DHAS to the mother resulted in a rapid marked rise in estradiol levels in MV (400% of control) and estrone levels in UV (1480% of control). The rise in estrone levels in MV was slower than that of estradiol. The increase in estradiol in UV and UA was significant, but the values were lower than that in MV. No significant changes in estriol levels in each compartment were demonstrated. However, a significant increase in estetrol was observed in each compartment by 4 hours. A significant correlation was found between individual MV and UV plasma estetrol concentrations. These results indicate that placenta secretes estrone and estradiol asymmetrically to maternal and fetal circulation after DHAS injection. Determination of the maternal estradiol and estetrol rise after DHAS injection may reflect placental and fetoplacental function, but estriol may not.