HRT is available in various forms. It generally provides low dosages of one or more estrogens, and often also provides either progesterone or a chemical analogue, called a progestin. Testosterone may also be included. In women who have had a hysterectomy, an estrogen compound is usually given without any progesterone, a therapy referred to as "unopposed estrogen therapy". HRT may be delivered to the body via patches, tablets, creams, troches, IUDs, vaginal rings, gels or, more rarely, by injection. Dosage is often varied cyclically, with estrogens taken daily and progesterone or progestins taken for about two weeks every month or two; a method called "sequentially combined HRT" or scHRT. An alternate method, a constant dosage with both types of hormones taken daily, is called "continuous combined HRT" or ccHRT, and is a more recent innovation. Sometimes an androgen, generally testosterone, is added to treat reduced sexual desire/(libido). It may also treat reduced energy and help reduce osteoporosis after menopause.HRT is seen as either a short-term relief (often one or two years, usually less than five) from menopausal symptoms (hot flashes, irregular menstruation, fat redistribution etc.) or as a longer term treatment to reduce the risk of osteopenia leading to osteoporosis. Younger women with premature ovarian failure or surgical menopause may use hormone replacement therapy for many years, until the age that natural menopause would be expected to occur.
Recent
Findings
According to a recent report citing early findings reported at a recent American
Academy of Neurology meeting, hormone therapy taken soon after menopause may
help protect against dementia, even though it raises the risk of mental decline
in women who do not take the drugs until they are older. Dementia risk was 1%
in women who started HRT early, and 1.7% in women who didn't, (e.g. women who
didn't take it seem to have had on average a 70% higher relative risk of dementia).
Another recent controlled, randomized study found HRT may actually prevent the
development of heart disease and reduce the incidence of heart attack in women
between 50 and 59, but not for older women. The mechanism may have something
to do with the contradictory effects of increasing propensity for clotting,
versus improving both "good" and "bad" cholesterol concentrations
in the blood (which would have a protective effect). Followup studies are being
performed which are intended to confirm these finding.(1)
source
: wikipedia