Testosterone & Male Hormone Tests
Answers to common questions about testosterone & male hormone tests.
Questions on this page
What is testosterone?
Testosterone is the major androgen in men and is important for:
- Sexual function
- Muscle mass
- Bone health
- Red blood cell production
- Overall reproductive function
When should testosterone be measured?
Testosterone is generally assessed in the morning, particularly when evaluating suspected testosterone deficiency.
Is one low testosterone result enough to diagnose low testosterone?
Usually not.
A low result generally needs confirmation with repeat testing, together with compatible symptoms and appropriate evaluation.
What is free testosterone?
Free testosterone is the fraction not tightly bound to proteins and can provide additional information in selected situations.
What is SHBG?
Sex hormone-binding globulin (SHBG) is a protein that binds testosterone and influences the amount of testosterone that is biologically available.
Why can total testosterone be normal but free testosterone be low?
Changes in SHBG can alter the relationship between total and free testosterone.