When you hear the word "testosterone," you probably know it as a hormone found in men. Although the word often is stereotypically associated with macho men who exhibit aggressive behavior and have huge amounts of muscle mass, those are characteristics of steroid-based testosterone, not natural testosterone, which has many functions in both men and women.
Testosterone is a hormone produced by the adrenal glands, testes and ovaries. The hormone is responsible for many male characteristics, such as hair growth, muscles, sex drive and a deeper voice. In females, it is essential for the proper functioning of the ovaries and libido and is necessary for bone strength.
According to the National Institutes of Health, the normal range of testosterone is 30 to 95 nanograms per deciliter (ng/dL) for women and 300 to 1,200 ng/dL for men, but individual laboratories might have a slightly different range that they consider normal. Also keep in mind that the levels vary with age. In women, the level of testosterone in the blood is lowest during puberty and adolescence, and is highest in pre- and post-menopausal women. For men, the levels increase during puberty and stay steady for much of their young adult life. They then slowly begin to decline during middle and older age.
The most common way to evaluate the levels of cholesterol is through a blood draw. According to the NIH, the most common reasons for evaluating testosterone levels are for the early onset of puberty for males, impotence, infertility, or the onset of male characteristics found in a female.
There are many possible causes of an abnormal test result if females. Hormonal problems, adrenal or pituitary gland problems, and ovarian diseases or cancers all can affect testosterone levels. Pregnant women have higher levels of testosterone than their non-pregnant counterparts. In males, abnormal levels are usually a result of testicular or adrenal gland problems.
If a female has too much testosterone, she can suffer from hair loss, unwanted hair growth, weight gain, aggressiveness, and irregular menstrual cycles. Symptoms of levels that are too low include fatigue, hot flashes, decreased sex drive, depression, amenorrhea and loss of muscle mass or strength. If you suffer from any of these symptoms, talk to your doctor about being tested.