The purpose of this study was to quantify the various sources of estrone (E₁) and 17β-estradiol (E₂) production i n normal men and in women with testicular feminization. The mean production rate of E₁ in four young adult men was 58 μg/ 24 h, while that of E₂ was 44 μg/24 h. In these men, E₁ production could be accounted for totally by extraglandular formation through 1) aromatization of plasma androstenedione, 2) conver(sion of E)2 which was formed from the aromatization of plasma testosterone, and 3) conversion of secreted E₂. In these men, only 12 μg or less of E₂ production could not be accounted for by extraglandular formation from plasma C19 precursors, and is presumed to have arisen by testicular secretion.

In six women with testicular feminization, the mean produc(tion rate of E₁ was 99 μg/24 h, while that of E)2 was 77 μg/24 h. The amount of E₂ production that arose by glandular secretion could be computed in four of these women and was considerably greater than that found in the young adult men. In these women with testicular feminization, an average of 44 μg/24 h E₂ could not be accounted for by extraglandular formation and is presumed to have arisen by testicular secretion.

The mean plasma production rate of testosterone in the normal men was 5.7 mg/24 h, while that in the women with testicular feminization was 8.3 mg/24 h. However, the range of plasma production rates of testosterone in the women with testicular feminization was large (1.3−17.0 mg/24 h). (J. Clin Endocrinol Metab49: 905, 1979)