Although testosterone is usually thought of as a male hormone, women also need it in small doses, according to the February issue of Mayo Clinic Women's HealthSource.
Women's ovaries and adrenal glands share the responsibility for testosterone production. Studies show that testosterone helps women maintain muscle and bone strength, and contributes to sex drive or libido.
Women manufacture about one-seventh the amount of testosterone each day that men do. After menopause or ovary removal, however, testosterone production drops much further. Estrogen replacement therapy can also lead to decreased testosterone production, leading some postmenopausal women to go to their doctors with concerns about lack of energy and libido despite already being on hormone replacement therapy.
When testosterone levels in the blood increase in testosterone-deficient women, bone density usually improves, and women generally report that they feel better.
Currently, the only way to replace testosterone in women is through an injection every two or three weeks, but a testosterone skin patch may be available in the future.