Menopause, a natural physiologic change that occurs in women in their late forties or early fifties, is characterized by loss of ovarian function and decline in estrogen production. Many peri-menopausal women experience a strong sensation of warmth/flushing often accompanied by profuse sweating (“hot flashes”). Many develop atrophic vaginitis, leading to painful intercourse and increased vaginal infections. Estrogen replacement therapy (ERT) was an accepted therapy to relieve symptoms of menopause.

As the role of estrogen in bone mineralization became clear, and the increased risk for osteoporosis that resulted from estrogen deficiency following menopause was appreciated, another indication for ERT appeared. Indeed, the use of ERT to prevent or delay the progression of osteoporosis is at least as important if not more important than the use of ERT to relieve menopausal symptoms. ERT, in conjunction with adequate intake of calcium and vitamin D, together with regular weight-bearing exercise (such as walking), helps to prevent bone loss and reduces the risk of fracture by up to 50%.

The benefit of ERT to lower the risk of coronary heart disease (CHD) is less well established. Current evidence suggests that the risks and benefits of ERT depend on the presence of risk factors and duration of therapy. Women with risk factors for CHD derive greater survival benefit from ERT than women without risk factors. While overall mortality in women using ERT, the survival benefit decreases over time.

In women who have a uterus, ERT should be accompanied by progestin therapy. Unopposed estrogen stimulation of the uterus, even after menopause, increases the risk of endometrial hyperplasia and cancer. A progestin is any substance, natural or synthetic, that affects some or all of the biological changes produced by progesterone. Progestins include synthetic derivatives of testosterone or progesterone.

Estrogen may be given for the first 25 days of each month (cyclic) or daily (continuous). Continuous daily estrogen is likely to improve compliance by preventing the return of vasomotor symptoms (e.g. hot flushes and profuse sweating) occasionally associated with a cyclic regimen. Women who experience ERT-related breast tenderness may prefer cyclic estrogen.

When a progestin is needed, it can be given for 12-14 days of each month (cyclic) or daily (continuous). Withdrawal bleeding occurs in most women treated with cyclic progestin regimens. The advantage of continuous combined HRT for most women is the earlier development of an atrophic endometrium than the cyclic regimen with more than 75% women taking continuous combined HRT regimens for at least 6 months achieving amenorrhea. However, the continuous combined HRT regimens are also associated with a higher incidence of irregular bleeding and spotting in the initial 3-8 months of therapy than with the cyclic regimens. Irregular bleeding and spotting is especially common in women who have only recently reached menopause but less in women starting HRT 3 years or more after menopause. For some women, unpredictable bleeding may be less desirable than the predictable withdrawal bleeding associated with cyclic HRT.

Some examples of oral ERT/HRT regimens are listed below:

The supply of the following products in Hong Kong has recently been discontinued by their respective distributors:

Ampiclox Suspension

Lodine SR 600mg Capsule

Lomotil Syrup

Motilium 10mg Suppository

Stoxil Cream

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