Effects of a continuous estrogen-progestogen therapy for climacteric symptoms on circulating sex steroids and gonadotrophins.

Twenty-six peri- and postmenopausal women with climacteric symptoms were given each day for 1 year a tablet containing 2 mg 17-beta-estradiol, 1 mg estriol and 1 mg norethisterone acetate. Blood samples were collected before, after 3 months and after 12 months of treatment and were analysed for their gonadotrophins, estradiol, estrone, testosterone, androstenedione content and for their SHBG binding capacity. Serum levels of estrone and androstenedione before treatment were found to be higher in the perimenopausal than in the postmenopausal group. An increase of serum estrogens concomitant with a decrease of gonadotrophins was noted. The estrone/estradiol ratios after 3 and 12 months of treatment were 5.3 and 4.7, respectively. A decrease in the serum concentration of testosterone and androstenedione was recorded during treatment. The reduction of gonadotrophins, especially LH, might have been responsible for the reduction in circulating androgens. The reduction of serum levels of androgens during the present long-term replacement therapy could be of metabolic importance.