The account of "neonatal sterilization" is the story of the advocates of direct effect of steroids on the gonads and those who believed in the indirect influence, mediated through the hypothalamus and/or the pituitary gland. As often happens in biology, both convictions represent the same image seen from different perspectives. Prof DC Johnson (Kansas City, KS) reminisced the beginning of the story in a letter to me. I am paraphrasing parts of the letter with his permission. "As a starting point we could pick the life-long research of Emil Steinach ... " Steinach recognized the influence of testes on the develop ment of accessory sex organs in 1894, described virilization of females and feminization of males in 1913, and identified the controlling influence of the hypophysis on the gonads in 1928. He reviewed his work in a book Sex and Life, Forty Years of Biological and Medical Experience (E Steinach and L Loebe!; Faber and Faber, London, 1940). He got on the wrong road in later years and that is the reason everybody seems to have forgotten him. He presented his hypothesis that estrogen has a direct effect upon the testes, i. e. hormone antagonism, at the 1st International Congress on Sex Research in 1926.
