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: 4-6 days. May take longer based on weather, holiday, or lab delays.
What This Test Measures
This test measures two distinct testosterone biomarkers: free testosterone (direct) and total testosterone (LC/MS). Free testosterone is the unbound, active form of the hormone that is available to act on cells in the body. Total testosterone reflects both unbound testosterone and testosterone bound to proteins such as SHBG or albumin, and is measured using LC/MS methodology for high analytical precision.
These are two separate, directly measured values rather than a single combined result. Free testosterone is measured directly (not calculated), and total testosterone is measured directly using liquid chromatography-mass spectrometry. Reporting one hormone result alone does not provide a complete picture of overall endocrine function, and results are best reviewed alongside your symptoms and medical history with a healthcare provider.
Benefits
- Measures both free (direct) and total testosterone levels
- Helps identify abnormally low or high testosterone
- Supports evaluation of possible infertility causes
- Helps monitor infertility treatment progress over time
- Supports monitoring for transgender men on hormone therapy
- Uses LC/MS methodology for total testosterone accuracy
Who Is This Test For?
- Individuals experiencing symptoms of low sex drive or erectile dysfunction
- Those exploring possible causes of infertility
- Individuals monitoring an ongoing infertility treatment plan
- Transgender men monitoring gender-affirming hormone therapy
- Those with unexplained muscle weakness or brittle bones
- Individuals noticing changes in body or facial hair growth
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 free testosterone (direct) and total testosterone in the blood. Free testosterone reflects the active, unbound hormone, while total testosterone reflects both bound and unbound testosterone, measured using LC/MS methodology. Together, these results may help a healthcare provider evaluate signs of a testosterone imbalance. This test does not diagnose a condition on its own.
2. Who would benefit from this test?
This test may be appropriate for individuals experiencing symptoms such as low sex drive, erectile dysfunction, or infertility, as well as those monitoring infertility treatment. It may also be used by transgender men monitoring gender-affirming hormone therapy. It is not intended to evaluate every hormone-related symptom.
3. When should I order this test?
You may consider ordering this test if you are exploring a possible cause of infertility, monitoring an infertility treatment plan, or tracking testosterone levels while undergoing gender-affirming hormone therapy. You may also consider it if you notice symptoms such as reduced sex drive, muscle weakness, or unexplained changes in body hair. This test does not replace a full medical evaluation.
4. How does this test differ from other hormone tests?
This test reports two directly measured values: free testosterone (direct) and total testosterone (LC/MS). Free testosterone reflects only the active, unbound hormone, while total testosterone reflects both bound and unbound testosterone. Both values are measured directly rather than calculated. This combination differs from tests that report only one form of testosterone, since it provides both the active and overall circulating amounts.
5. Do I need to fast before this test?
No special preparation is required for this test.
6. How quickly will I get results?
Results are typically available in 4-6 days. Results may take longer based on weather, holidays, or lab delays.
7. How do I interpret the results?
Interpreting testosterone results depends on factors such as your symptoms, medical history, sex, age, and any medications or supplements you take. Free and total testosterone provide different information and are not interchangeable, so both figures are typically reviewed together. Results are often considered alongside other clinical findings rather than on their own. One abnormal result does not automatically confirm a hormonal condition, and one normal result does not 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 results fall outside the expected range, review them with a qualified healthcare provider. They can help determine whether additional evaluation or testing is appropriate based on your health history and symptoms. This test result alone does not provide a complete clinical conclusion.
9. How often should I get tested?
Testing frequency should be determined as directed by your healthcare provider, based on your individual health needs and the purpose of testing.
Pre test preparation
No special preparation is required. Stop biotin supplements for at least 72 hours before testing, as biotin may interfere with test results.
