Maternal and amniotic fluid steroids throughout human pregnancy.

Concentrations of testosterone, dihydrotestosterone, androstenedione, progesterone, 17 alpha-hydroxyprogesterone, and estradiol were measured by radioimmunoassay in the amniotic fluid and maternal peripheral blood obtained from normal pregnancies between 14 and 40 weeks of gestation. There was a sex difference in the levels of all the androgenic steroids in the amniotic fluid before 20 weeks with higher levels in pregnancies with male fetuses. Amniotic fluid 17 alpha-hydroxyprogesterone levels were significantly elevated in a pregnancy with the fetus affected with congenital adrenal hyperplasia. The levels of all the steroids in the amniotic fluid were significantly elevated in the pregnancy with molar degeneration of the placenta. There was a sex difference in the levels of dihydrotestosterone in the maternal peripheral blood before 20 weeks with higher levels in pregnancies with male fetuses. There was no correlation between the steroid levels in the maternal serum and amniotic fluid even though most of the samples of maternal serum were drawn at the same time as amniocentesis.