Serum Steroids and Pituitary Hormones in Infants with Particular Reference to Testicular Activity

Abstract

We have determined the concentrations of pregnenolone, progesterone, 17-hydroxyprogesterone, androstenedione, dehydroepiandrosterone, testosterone, 5α-dihydrotestosterone, and androsterone in serum collected from 34 boys and 11 girls between 5–40 weeks of age, and we have compared these data with the concentrations of FSH, LH, and PRL in the same samples. Clear sex differences in the serum concentrations of testosterone and 5α-dihydrotestosterone were found to exist between 5–25 weeks of age, and during this period the serum concentrations of these steroids in the male infant population are similar to those in the lower normal adult male range. This sex difference is indicative of a high level of testicular steroidogenesis, which was also supported by the higher serum concentrations of 17- hydroxyprogesterone in boys compared to girls, between 10-25 weeks of age, and the good correlation between serum concentrations of 17-hydroxyprogesterone and testosterone in these boys. High serum concentrations of 5a-...