Quick Facts
- Sample: Blood (Morning collection 7am-10am)
- Fasting: No special preparation is required. Stop biotin supplements for at least 72 hours before testing, as biotin may interfere with test results.
- Turnaround: 4-7 days. May take longer based on weather, holiday, or lab delays.
(LabCorp Only) Any result in excess of 1500 will be reported as >1500.
What This Test Measures
This test measures two separate biomarkers: Free Testosterone (Direct) and Total Testosterone. Free testosterone is the unbound, active form of testosterone that is available to interact with receptors in your cells. Total testosterone reflects both the unbound testosterone and the testosterone that is bound to proteins in your blood, such as SHBG or albumin.
Because free and total testosterone are reported separately, this test lets you and your healthcare provider see the active hormone level alongside the overall circulating level. Total testosterone in this test is measured using mass spectrometry (MS) methodology. These are two distinct measurements of the same hormone, not two different hormones, and neither result alone represents your complete testosterone picture.
Benefits
- Reports both free and total testosterone from a single blood draw
- Helps identify abnormal testosterone levels or hormone imbalance
- Supports evaluation of possible causes of infertility
- Can help monitor infertility treatment progress
- Useful for monitoring testosterone therapy in transgender men
- No fasting or special preparation required
Who Is This Test For?
- People experiencing loss of sex drive or low libido
- People with erectile dysfunction who want to check hormone levels
- Individuals being evaluated for possible causes of infertility
- Individuals monitoring an ongoing infertility treatment plan
- Transgender men monitoring testosterone during gender-affirming hormone therapy
- People with unexplained muscle weakness, brittle bones, or anemia
How It Works
- Order Your Test Online
- Visit a Local Lab
- Get Results Online
FAQ
1. What is the purpose of this hormone test?
This test measures two related but distinct testosterone values: free testosterone (direct) and total testosterone. Free testosterone reflects the active, unbound hormone circulating in your blood, while total testosterone reflects both bound and unbound testosterone combined. Together, these results may help a healthcare provider evaluate a possible testosterone deficiency or hormone imbalance. This test does not diagnose a condition on its own.
2. Who would benefit from this test?
This test may be considered by people who want a clearer picture of both their active and overall testosterone levels. This can include individuals being evaluated for infertility, those monitoring infertility treatment, and transgender men monitoring testosterone during gender-affirming hormone therapy. Whether this test is appropriate depends on your individual health history and should be discussed with a healthcare provider.
3. When should I order this test?
You might consider this test if you want to evaluate both free and total testosterone at the same time, such as when investigating a possible hormone imbalance, evaluating infertility, or monitoring an existing infertility treatment or testosterone therapy plan. This test does not replace a full medical evaluation, and results are best reviewed with a healthcare provider.
4. How does this test differ from other hormone tests?
This test reports both free testosterone (direct) and total testosterone, rather than only one form. Free testosterone is the unbound, biologically active portion, while total testosterone includes testosterone bound to proteins like SHBG or albumin along with the unbound portion. A test that reports only free or only total testosterone would not give you both values, and this distinction matters because free and total levels are not interchangeable.
5. Do I need to fast before this test?
No special preparation is required for this test. Avoid biotin supplements for at least 72 hours before testing, as biotin may interfere with test results.
6. How quickly will I get results?
Results are typically available in 4-7 days. Results may take longer based on weather, holidays, or lab delays.
7. How do I interpret the results?
Interpreting free and total testosterone results depends on factors such as your age, sex, symptoms, medical history, and any medications or hormone therapy you are using. Free and total testosterone are two different measurements and should not be interpreted as interchangeable. These results are often reviewed alongside your symptoms and, when relevant, other hormone measurements. An abnormal result does not automatically confirm a hormonal condition, and a normal result does not automatically rule one out.
Disclaimer: Reference ranges may vary by laboratory. Listed ranges are general guidelines and may differ from those used by the performing lab. Always consult your healthcare provider for interpretation.
8. What should I do if my results are abnormal?
If your free or total testosterone results fall outside the expected range, review them with a qualified healthcare provider. They can help interpret what the results may mean in the context of your health history and symptoms, and determine whether any additional evaluation or testing is appropriate.
9. How often should I get tested?
There is no set schedule for repeat testing. How often you should be tested depends on your individual health situation and should be determined as directed by your healthcare provider.
Pre test preparation
No special preparation is required.
