A testosterone test measures the amount of the male hormone, testosterone, in the blood. Both men and women produce this hormone.
The test described in this article measures the total amount of testosterone in the blood. Another test measures what is called "free" testosterone.
A blood sample is needed. For information on how this is done, see: Venipuncture
The recommended time of day to have a blood sample taken for this test is between 7 a.m. and 10 a.m. It may need to be repeated a second time.
The health care provider may advise you to stop taking drugs that may affect the test.
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
This test may be done if you have symptoms of abnormal male hormone (androgen) production.
In males, the testicles produce most of the testosterone in the body. Levels are most often checked to evaluate signs of low testosterone:
In females, the ovaries produce most of the testosterone. Levels are most often checked to evaluate signs of higher testosterone levels:
Note: ng/dL = nanograms per deciliter
The examples above are common measurements for results for these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different specimens.Talk to your doctor about the meaning of your specific test results.
Increased testosterone levels may mean:
Decreased production of testosterone:
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include:
Swerdloff RS, Wang C. The testis and male sexual function. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 242.