Plasma estradiol-17 beta as an index of fetoplacental function.

Serial plasma unconjugated estradiol-17 beta was measured by a radioimmunoassay method in 26 cases of hypertensive disorder of pregnancy, 13 cases of poor obstetric history and 4 cases of intra-uterine growth retardation. There was considerable overlap of hormonal values between pregnancies, resulting in delivery of normal fetuses and those with dysmature fetuses. Serial estimation of estradiol-17 beta were not found to be useful in the prediction of intra-uterine death, although low values were obtained after fetal death has occurred. Estradiol-17 beta estimation appeared to be an unreliable index of fetoplacental function.