Hormone replacement therapy
Hormone Replacement Therapy (HRT) is a regime of hormones taken by a person in order to supplement hormones they lack or are low in.
Commonly, HRT is prescribed by doctors for menopausal women to replace lost estrogen. This is a sex hormone produced by the female gonads (ovaries) that stops functioning at the time of menopause. Women going through menopause are sometimes prescribed HRT to replace this lost estrogen in order to aid the menopausal symptoms, or to reduce the risk of osteoporosis later in life. Estrogen loss can cause this, as it is a major factor in the absorption of calcium in the body, which builds bones.
Common hormones used in HRT can include estrogen, testosterone and progestin. Typically for a transsexual, these are used in conjunction with hormone blockers for the hormone that does not correspond to their gender; for example a male-to-female transsexual taking androgen (testosterone is an androgen) blockers with estrogen.