Hysterectomy, oophorectomy, and endogenous sex hormone levels in older women: The Rancho Bernardo study

This study examines the cross-sectional association of hysterectomy and oop horectomy status, chronological age, and years since menopause with plasma levels of total and bioavailable testosterone and estradiol, androstenedion e, estrone, and sex hormone-binding globulin(SHBG) in community-dwelling po stmenopausal women who were not using estrogen replacement therapy. Six hun dred and eighty-four women, aged 50-89 yr, were surveyed for hysterectomy a nd oophorectomy status and had plasma obtained between 1984-1987. Of these, 458 (67%) had not undergone hysterectomy or oophorectomy (intact), 123 (18 %) reported hysterectomy with bilateral oophorectomy, and 123 (18%) reporte d hysterectomy with conservation of I or both ovaries. After adjustment for age and body mass index, both total and bioavailable t estosterone levels were reduced by more than 40% (P < 0.001) in hysterectom ized women with bilateral oophorectomy compared to those in intact women, w ith intermediate levels observed in hysterectomized women with ovarian cons ervation. Androstenedione levels were about 10% lower in hysterectomized wo men with or without ovarian conservation compared to those in intact women (P = 0.039). Total estradiol levels tended to be lower (P = 0.095) in bilat erally oophorectomized women. Levels of bioavailable estradiol, estrone, an d SHBG did not differ by hysterectomy and oophorectomy status. Among intact women, total, but not bioavailable, testosterone levels increa sed with age (P = 0.015), reaching premenopausal levels for the 70-79 decad e with relatively stable levels thereafter. Among oophorectomized women, to tal and bioavailable testosterone levels did not vary with age and were 40- 50% lower than those in intact women throughout the 50-89 yr age range. And rostenedione levels decreased 27% and SHBG levels increased 30% (P < 0.001) with age in intact, but not oophorectomized, women. Levels of other hormon es did not vary with age. Stratification by years since menopause or surger y yielded similar results. These results demonstrate that the postmenopausal ovary remains a critical source of androgen throughout the lifespan of older women. The clinical con sequences of lower testosterone levels years after oophorectomy are unknown . Reconsideration of prophylactic oophorectomy and clinical trials to evalu ate the effects of androgen replacement after oophorectomy are needed.