Estrogens in maternal plasma following intraamniotic injection of (3H)-dehydroepiandrosterone-sulfate in midpregnancy.

In 4 patients with normal pregnancies between the 18th and 20th week of gestation (3H7alpha)-dehydroepiandrosterone-sulfate ([H]-DHEA-S) was injected intraamniotically. Maternal venous blood was drawn before and at regular intervals for 240 minutes after DHEA-injection. Thereafter, legal abortion was performed by intraamniotic instillation of prostaglandine. The conjugated steroids were hydrolyzed enzymatically and the total steroids were isolated and identified. The following labelled metabolites were determined quantitatively: Estriol (e3, estradiol-17beta (E2-17beta), estrone(E1), 16alpha-hydroxy-estrone, (16alpha-OH-DHEA), ALPHA4-androstenedione (AD) and testosterone (T). The maximal increase of all estrogen fractions in matermal plasma occurred 120-180min after intraamniotic injection of the precursor. The most prominent rise of the C18-steroids could be shown for estriol. 60-70% of all metabolites were C16-hydroxylated.