Effect of estrogens and progesterone on gonadotropin and prolactin release in a patient with androgen insensitivity.

Response of serum levels of gonadotropins and prolactin to doses of estrogen and progesterone was measured in a patient with the complete form of androgen insensitivity, ie, testicular feminization. Before gonadectomy a single 2.5-mg dose of estradiol benzoate (E2B) produced a decrease in gonadotropin levels. Gonadectomy resulted in a rise of serum levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) but had no effect on levels of prolactin. The following results were obtained after gonadectomy: During low-dosage therapy with ethinyl estradiol (EE) a single 2.5-mg dose of E2B produced a decrease in FSH and LH levels, no LH surge, and a small rise in prolactin levels. With a tenfold higher EE priming, the same dose of E2B provoked an LH surge; progesterone administration produced FSH, LH, and prolactin release. However, progesterone priming blocked the positive feedback of estradiol and enhanced its negative feedback. Pituitary sensitivity ot nonandrogenic steroids appears to be normal in cases of testicular feminization. Under this condition, after gonadectomy, the dynamics of gonadotropins and prolactin in response to estrogens or progesterone administration are similar to those in normal women and suggest that aromatization products of testosterone do not produce any irreversible effects on neuroendocrine differentiation of androgen-insensitive patients