Estrogen formation in vitro by fetoplacental tissues of midpregnancy

Abstract

Midterm placenta and the placenta plus fetal tissues, including adrenal, liver, ovary, lung, kidney, and skin, were incubated separately with dehydroepiandrosterone (DHA)-7α-3H. Estrone, estradiol-17β, and estriol were identified in each incubate. The midterm placenta was active in converting DHA to estrone (40.9 per cent) and estradiol (16.3 per cent). The conversion of DHA to estriol was much lower (0.40 per cent). In the incubate of placenta plus fetal liver, the estriol yield was definitely higher (18.3 per cent) than that of other incubates. The conversion of DHA-3H to estrogens in other incubates of fetal tissues in combination with placenta or placenta alone was not remarkably different. These findings suggest that the fetal liver in association with the placenta plays an important role in estriol formation during midterm pregnancy.