About the Test
Purpose of the test
The purpose of testosterone testing is to evaluate the amount of the hormone in the blood. Testosterone levels that are outside of a normal range can cause changes to health and physical appearance. Measuring testosterone can help diagnose medical conditions or monitor your response to therapy:
- Diagnosis Doctors may check testosterone levels to determine the cause of your symptoms. Testing can help identify deficiency or an elevated level of testosterone. Tests may be part of assessing if you have health conditions that can affect hormone levels.
- Monitoring This is how doctors follow your health over time. If you have had abnormal testosterone tests, follow-up testing may be used to track your testosterone levels.
Testosterone tests can also monitor the health of transgender men who were assigned female at birth but identify as male. Some transgender men may take hormone therapy to change their physical appearance to match their gender identity. Doctors may monitor testosterone levels in this group of men to ensure testosterone levels are maintained at a certain level.
What does the test measure?
A testosterone test measures the level of the hormone testosterone in the blood.
In men or anyone with a penis, testosterone is produced by the testicles and the adrenal gland, controlling the development of sperm and male sex characteristics. And in women or anyone with ovaries, testosterone is produced by the ovaries, the adrenal gland, and other tissues, and it aids in overall growth and development.
Testosterone in the blood can be either bound or free:
- Bound testosterone is attached to proteins such as albumin or sex hormone-binding globulin (SHBG). Most testosterone is bound to SHBG.
- Free testosterone, the active form, is all the remaining testosterone that is not bound to other substances.
A total testosterone test measures both bound and free testosterone in a blood sample. This is the most common type of testosterone test, and levels are commonly reported in nanograms per deciliter of blood (ng/dL). Less often, a test may be performed for free testosterone, which is reported in picograms per deciliter of blood (pg/dL).
Another less common test is for bioavailable testosterone, which can be used more readily by the body. This is all testosterone that is not bound to SHBG, including free and albumin-bound testosterone. Bioavailable testosterone is also commonly reported in ng/dL.
When should I get this test?
Your doctor may order a testosterone test if you are experiencing symptoms that suggest hormone levels outside of a normal range.
In men or anyone with a penis, a testosterone test may be performed if you have symptoms that suggest a low testosterone level, such as:
- Early or late onset of puberty
- Erectile dysfunction
- Fertility problems
- Osteoporosis or thinning of the bones
- Decrease in sex drive
Even if you don’t have symptoms doctors may also evaluate your testosterone levels if you have a health condition that can affect hormone levels. For example, testosterone testing may be performed if you have HIV/AIDS, unexplained bone density loss, infertility, or anemia. If you have undergone certain types of cancer treatment, such as chemotherapy or radiation to the testicles, you may also have your testosterone levels checked.
Doctors may check testosterone levels as part of a diagnostic work-up in women or anyone with ovaries if physical changes suggest a higher-than-normal testosterone level. Changes may include the following:
- Irregular periods
- Loss of periods
- Changes in hair growth patterns
- Voice changes
- Skin changes such as oily skin or acne
- Enlarged clitoris
You may also have testosterone testing if you are a transgender man on masculinizing hormone therapy intended to induce and maintain male sex characteristics. Testing is recommended every three months during the first year of therapy as your dose is adjusted. After that, your doctor may suggest monitoring your testosterone levels one to two times per year.
If you have questions about testosterone testing, talk with your health care provider, who can discuss whether this testing is appropriate in your situation.
Finding a Testosterone Test
How can I get a testosterone test?
Testosterone testing requires a blood draw ordered by a doctor. The blood sample is usually taken during a visit to a doctor’s office, clinic, lab, or hospital. This sample is then sent to a laboratory for analysis.
Can I take the test at home?
Several at-home collection test kits for checking testosterone levels are available without a prescription. These test kits may be sold at your local pharmacy and are available online.
Self-collection kits contain all the materials needed to obtain a blood or saliva sample and mail it to a laboratory for testing. Results from at-home testosterone tests are usually available within a few days.
If you have concerns about your testosterone levels, it is important to talk with a health care provider. At-home testosterone testing doesn’t replace talking with a doctor, especially if you have a change in your health.
If the results of an at-home test are abnormal or if you are having symptoms, your doctor might want to order another testosterone test. They may also suggest a physical exam or other types of tests to assess your overall health.
How much does the test cost?
Costs for testosterone testing may include charges for an office or clinic visit, a fee for the technician to draw your blood, and laboratory fees when the sample is analyzed.
If your doctor recommended testing, the costs of measuring your testosterone level are generally covered by health insurance. Depending on your insurance plan, you may be responsible for some out-of-pocket costs like copays or a deductible. If you have questions about the cost of testing, you can speak with your doctor and insurance plan for more information.
Taking a Testosterone Test
Testosterone levels are checked by drawing a blood sample from a vein in the arm. The sample is usually taken in a doctor’s office, medical clinic, laboratory, or hospital.
Before the test
Testosterone testing should be performed between 7 a.m. and 10 a.m., which is around when levels are normally the highest. Some doctors may require you to prepare for the test by fasting, which means avoiding eating or drinking anything but water for a few hours before the test. Other doctors may not require you to fast before testosterone testing.
Check with your doctor about how to prepare for your testosterone test, and carefully follow any instructions before the test.
During the test
Your doctor or another health professional will draw a sample of blood using a small needle. The blood is normally drawn from a vein inside your elbow.
An elastic band, called a tourniquet, will be placed around your upper arm so more blood is in the vein. The inside of your elbow will be cleaned with an antiseptic wipe to prevent infection. A needle will be inserted into the vein to fill a small vial with blood.
During the test, you might feel a slight sting as the needle is inserted or removed. The entire process usually lasts less than a minute or two.
After the test
Once the blood draw is complete, you may be asked to apply pressure around where the needle was inserted using gauze or cotton. This can help reduce swelling, bleeding, and bruising. You may also be given a cotton swab or bandage to cover the area.
The type of blood draw used to gather a sample for a testosterone test is routine. It is usually done on an outpatient basis, and you can resume your normal activities following testing. If you were told to fast before testing, you may wish to bring a light snack to eat once the test is complete.
Testosterone Test Results
Receiving test results
You will generally receive results showing your testosterone levels within several days. Your results may be uploaded to an online health portal for viewing or sent to you in the mail.
In some cases, your doctor may also contact you to discuss your results. They may suggest a follow-up appointment to review your test results and discuss the next steps in your medical care.
Interpreting test results
There are several measures of testosterone, and the interpretation of test results depends on which kind of testosterone was measured.
Total testosterone is the most commonly used test for diagnostic and monitoring purposes. Total testosterone results are typically reported in ng/dL.
Each result on your report has a corresponding reference range. This range shows what the laboratory considers to be an expected total testosterone level for a healthy person. Reference ranges can vary from laboratory to laboratory, so it is important to speak with your doctor about your result and what it means for your health.
Levels outside of the reference range can indicate a health problem. While testosterone levels decrease with age, abnormally low levels that occur alongside symptoms can indicate testosterone deficiency. In addition, low levels of testosterone in men or anyone with a penis can be tied to other health issues, including changes in thyroid function, genetic or chronic illness, benign tumors, problems with the testicles, obesity, or disturbed sleep.
In women or anyone with ovaries, abnormal testosterone levels can indicate excess testosterone produced by the ovaries or other glands that produce hormones. For example, abnormal testosterone results may be caused by polycystic ovary syndrome (PCOS), cancer of the ovary or adrenal gland, or a pituitary gland disorder.
Total testosterone levels alone are not enough to diagnose any health condition. Test results are interpreted in the context of your specific health situation. Your doctor may recommend repeat testing or additional tests to learn more about what may be causing your symptoms and/or the change in your testosterone level.
If you have a free or bioavailable testosterone test, it is important to talk with your doctor about what the test results mean. When prescribed, these tests are often interpreted in relation to total testosterone. If you have certain health conditions or take some medications, free or bioavailable testosterone tests may provide more detailed information about whether hormone levels in the body are normal.
The following questions may be helpful when reviewing your testosterone test results with your health care provider:
- What was the result of my testosterone test?
- If my test result was abnormal, do I need any follow-up tests?
- If follow-up tests are needed, what tests will be performed?
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