Postmenopausal Hormone Therapy

Estrogens and progestins used for postmenopausal hormone therapy are among the most commonly prescribed medications in the U.S. Currently, 46% of women who have experienced a natural menopause and 71% of women who have had bilateral oophorectomy report having used postmenopausal hormone therapy.7 The average duration of use in the U.S. as of 1992 was 6.6 years, but only 20% of users had maintained treatment for at least 5 years.

Selection of Patients for Treatment

-Women Under Age 40 (Castrates and Women With Gonadal Dysgenesis)

In these women, the duration of estrogen deprivation is prolonged, and in women after surgical menopause the loss of estrogen is acute. The cyclic use of estrogen is recommended for short-term reduction of vasomotor symptoms and for long-term prophylaxis against cardiovascular disease, osteoporosis, and target organ atrophy. In some young patients, the equivalent of 0.625 mg conjugated estrogens is insufficient to allow menstrual bleeding. Because women of this age ordinarily are exposed to estrogen levels that stimulate endometrial growth and withdrawal bleeding, and for psychological reasons, a higher dose should be considered, if necessary, to maintain withdrawal bleeding until the menopausal time of life. However, in our experience, the doses equivalent to 0.625 mg conjugated estrogens almost always suffice. A standard sequential program is utilized. In those patients castrated because of endometriosis, recurrence of endometriosis has very rarely been a problem with estrogen therapy, but because endometrial cancer has been reported to occur in remaining endometriosis exposed to unopposed estrogen, an estrogen and progestin combination is strongly recommended.

- The Perimenopausal Transition Years

After exclusion of other gynecologic causes, dysfunctional uterine bleeding is treated by progestin or oral contraceptive therapy and, if necessary, biopsy surveillance. Vasomotor reactions appearing in women despite the presence of menstrual bleeding should receive careful evaluation. Abnormal thyroid function should be ruled out. If a follicle-stimulating hormone (FSH) level is not greater than 20 IU/L, serious consideration should be directed toward psychosocial reasons for the flushing response.

The risk of fracture from osteoporosis will depend on bone mass at the time of menopause and the rate of bone loss following menopause.8 Although the peak bone mass is influenced by heredity and endocrine factors, it is now recognized that there exists only a relatively narrow window of opportunity for acquiring bone mass. Almost all of the bone mass in the hip and the vertebral bodies will be accumulated in young women by late adolescence (age 18), and the years immediately following menarche (11–14) are especially important. After adolescence, there continues to be only a slight gain in total skeletal mass that ceases around age 30, and in many individuals a decline in bone mass in the hip and spine begins after age 18.10, 11 After age 30 in most people, there is a slow decline in bone mass density, about 0.7% per year. The importance of a normal diet and a normal hormonal environment during adolescence cannot be overrated.

Meaningful perimenopausal bone loss that is secondary to a decrease in estrogen is limited to those women with fluctuating hormonal and menstrual function, irregular bursts of follicular function alternating with no ovarian response to gonadotropins, so that these women are exposed to low estrogen over significant periods of time. The bone loss that begins in the 20s is due to a mechanism that is independent of hormones, and longitudinal studies have documented that trivial amounts of bone are lost prior to menopause in women with adequate estrogen levels.

The Early Postmenopause

The long-term postmenopausal use of hormone therapy depends heavily on a woman's own informed assessment, a process that should occur at this point in life. An understanding of hormone therapy is an important component in any preventive health program directed toward the postmenopausal years. As a result of immediate responses in early climacteric symptoms, the patient enters the postmenopausal period of life more confident of herself emotionally, sexually, and physically. In our view, this establishes or cements good patient-clinician interchange and relations. The follow-up of the patient on effective estrogen-progestin therapy is more secure and certain. The practitioner offering estrogen-progestin treatment has a better and more reliable opportunity to act as primary clinician for these aging women. All monitoring of health systems will be improved as a result of this single involvement.

The Late Postmenopause

Atrophic conditions can be effectively treated with local or oral therapy in low maintenance doses. If there is no apparent basis for osteoporosis other than aging and ovarian failure, estrogen-progestin therapy and calcium plus vitamin D supplementation are advisable even for very old women. Further loss of bone can be halted and the risk of fractures reduced. In these older women, an assessment of progress can be obtained by measuring bone density. The impact of initiating hormone therapy in elderly women on the risk of cardiovascular disease has not been ascertained. However, it makes sense that elderly women would benefit from estrogen's dynamic protective mechanisms with an impact on stress incontinence, and probably, on the risk of Alzheimer's disease, as well.

Clinical Gynecologic Endocrinology and Infertility 6th ed: Leon Speroff, Robert H. Glass, Nathan G. Kase, 1999 Lippincott Williams & Wilkins