A New Era
The 1923 isolation of estrogen, the female sex hormone manufactured in both sexes, lead to a new era for menopausal women. Estrogens were first tried as an aid to menopausal women in the 1930s, but negative side affects cut short the effort. By the 1960s, a palatable estrogen supplement was developed. The substance was heavily promoted as a medication to keep menopausal women "feminine forever" (also the title of a 1965 book by Robert A. Wilson promoting estrogen therapy). Estrogen was promoted as a cure for hot flashes, urogenital dryness, and even mental illness.
However, in 1975, studies emerged linking estrogen with an elevated risk of endometrial cancer, and use of estrogen supplements dropped. Use of estrogens dropped considerably until researchers explored using estrogen with progesterone as a combined therapy. This combination is thought to reduce the risk of endometrial cancer.
Since the early 1980s, the use of synthetic hormones for menopause has climbed dramatically. In 1980, 12 million prescriptions were written for estrogen supplements. By 1993, a total of 48 million prescriptions were written. As estrogen has become used more widely, various benefits and risks have become apparent. Risks of using hormone replacement therapy include the development of gallstones, the development of blood clots, and an elevated risk of breast cancer among women who use estrogen supplements for long periods of time. More careful, standardized research needs to be done, particularly to understand the association between duration of hormone replacement therapy, dose of hormone replacement therapy, type of hormone replacement therapy, and risk of breast cancer. Negative side effects of the estrogen-progesterone combination are commonly reported. These include headaches, depression, and bloating. One sign of the distaste with which many women view the estrogen-progesterone combination is that the average use of estrogen replacement prescriptions is nine months.
On the positive side, estrogen supplements have been shown to reduced the risk among women of heart disease, the leading cause of death among men and women and a far more likely cause of death than endometrial cancer. Research suggests that estrogen lowers total cholesterol and relaxes blood vessels, making the heart's job easier. Studies have also shown that estrogen supplements cut the risk of osteoporosis, a disease in which bones become brittle and easily broken. Several small studies suggest that estrogen may also increase short-term memory.