Although testosterone is widely known as the "male hormone," it actually plays an important part in the development and function of the heart, brain, bones, muscles and blood vessels in both sexes. When testosterone levels are in the normal range for your sex, they signal your body to produce appropriate gender-specific features like genitalia, appropriate fat distribution and patterns of body hair.
Where It Comes From
Your pituitary gland is the master control center for testosterone production. When testosterone levels are too low, the pituitary gland releases a hormone called luteinizing hormone or LH. After it travels through the bloodstream, LH triggers the production of more testosterone from the adrenal glands as well as your ovaries. The pituitary gland continues to monitor the increased testosterone level and can start the production cycle all over again when necessary.
Indications for Blood Test
Your doctor may order a blood testosterone test if she is concerned that you have symptoms caused by abnormal testosterone levels. In women, these include hirsutism or excess body hair, male-related characteristics like a deep voice, menstrual irregularities and infertility. You'll need to go to a medical laboratory to have your blood drawn for this test, but there's no special preparation needed before the test, says Lab Tests Online.
Pre-Menopausal Levels
Testosterone levels in females are lowest during childhood and start going up at the beginning of puberty, according to MayoClinic.com. You can expect your testosterone level to peak when you're a teenager or young adult and then drop about 1 percent a year after age 30, states the University of Michigan Health System. From 14 to 17 years of age, a normal testosterone level for females is eight to 53 nanograms per deciliter or ng/dL. Throughout adulthood, you'll have 10 to 70 ng/dL of testosterone in your blood until you reach menopause.
Post-Menopausal Levels
If you're a woman who has gone through menopause, you'll have lower levels of sex-related hormones such as estrogen and testosterone. Typically, you can expect a normal testosterone level of 40 ng/dL for the rest of your life, says the University of Michigan Health System.
Expert Insight
While some women consider testosterone supplements to improve sex drive or overcome sexual dysfunction after menopause, MayoClinic.com states, "The long-term safety of testosterone therapy for women is unknown."
