Until the recent media attention on the high-level track athlete Caster Semenya, who is barred from competing because of high testosterone levels, this hormone was primarily perceived as a male-only hormone.
It is actually an important hormone for women too, helping to produce new blood cells, maintain bone health and libido, and boost other reproductive hormones. Women typically have naturally lower levels of testosterone, falling in the range of 9–55 ng/dL while men fall in the 300–1000 ng/dL range.
There are biological causes for increased testosterone in women. One such cause may be polycystic ovary syndrome (PCOS), a condition in which the ovaries or adrenal glands produce more male hormones than normal. Some 10 percent of women have PCOS, which can interfere with a woman’s menstrual cycle and create infertility issues. “Measuring testosterone concentrations is a very common test to aid in PCOS diagnosis and can be useful when investigating the cause of infertility,” says Joely Straseski, PhD, medical director of endocrinology at ARUP. Despite the name (polycystic), women may or may not have cysts on their ovaries.
Too much testosterone can also indicate the presence of tumors on the adrenal gland or ovaries—the main production center for these hormones in women. For men, the testes and adrenal glands are the main producers. While testosterone levels typically decline in both women and men with age, menopause can produce deceptive results. “In post-menopausal women, testosterone levels may appear higher because estrogen declines and the balance is skewed,” says Straseski, who is also an associate professor of pathology at the University of Utah School of Medicine.
“Measuring testosterone concentrations is a very common test to aid in PCOS diagnosis and can be useful when investigating the cause of infertility.”
Medical Director, Endocrinology
A condition known as intersex is another cause for higher than normal testosterone levels in women. Intersex is when a person possesses both sex organs (e.g., a person may have female genitalia but also possess testicular tissue internally). The two-time Olympic champion Semenya, mentioned earlier, is an intersex athlete.
Women who produce exceptionally high levels of testosterone may experience signs of virilization—the development of male physical characteristics (i.e., muscle bulk, body hair on the face, chest, or back, deepening of the voice).
Measuring testosterone levels requires a simple blood test and is often performed in the morning when testosterone levels are highest. The blood is sent to a laboratory that specializes in hormone testing where specific methods are used to produce the most accurate results possible.