Menopause and hormone replacement therapy
Menopause
- Definition. The permanent cessation of menstruation for 12 months caused by the termination of ovarian follicular recruitment, selection and development in the presence of elevated pituitary gonadotropin (follicle-stimulating hormone [FSH], luteinizing hormone [LH]) levels.
- Age. Average age is 51.4 years and may be genetically predetermined.
- Risk factors for early menopause include cigarette smoking and surgery (hysterectomy).
Climacteric (perimenopause)
- Definition. The transition period before the menopause from the reproductive stage of life to the postmenopausal years. Signs and effects of the menopause transition can begin as early as age 35, although most women who become aware of the transition do so about 10 years later, often in the mid to late 40s. The actual duration and severity of perimenopause in any individual woman cannot be predicted consistently in advance or during the process.
- Symptoms include weight gain, especially in the lower abdomen, buttocks, and thighs. This is theorized by some authorities to be bodily adaptation in humans to retain what little estrogen is left in the body (estrogens are fat soluble), and to protect the long bones as estrogen levels decrease and the risk of osteoporosis increases.
- Menstrual irregularities. Ten percent of women cease menstruating abruptly, but the vast majority experience 4–5 years of varying cycle length due to progressive ovarian failure.
- Hormone production. Initially characterized by elevated FSH and decreased inhibin levels, but normal levels of estradiol-17β and LH. However, there is wide individual variation.
Postmenopausal ovarian physiology
