Testosterone
Also known as: Total testosterone, Male hormone test, testosterone test, mardana hormone test
Measures total testosterone, the main male sex hormone. Women also make small amounts.
Why it's ordered
In men: low sex drive, erectile problems, infertility, loss of body hair or muscle, and tiredness. In women: excess facial or body hair, acne and irregular periods, for example in polycystic ovary syndrome (PCOS).
Preparation
In men, the test should be done in the morning (around 7–10 am), ideally fasting, because levels are highest then. A low result should be repeated on another morning before any diagnosis.
Typical adult values
| Men (morning) | about 300–1000 ng/dL (about 10–35 nmol/L) |
|---|---|
| Women | about 15–70 ng/dL (about 0.5–2.4 nmol/L) |
Ranges vary between labs and methods. Always use the range printed on your report.
If it's high
In women, high testosterone is most often due to PCOS; very high levels, especially with rapid hair growth or a deepening voice, need prompt assessment. In men, high levels are often from testosterone injections or supplements.
If it's low
Low testosterone in men can be caused by obesity, diabetes, serious illness, some medicines, poor sleep, or problems with the testes or pituitary gland. Low testosterone is diagnosed only when symptoms are present and morning levels are low on more than one test.
Good to know
Testosterone falls slowly with age. Testosterone treatment should not be started without a confirmed diagnosis, as it can reduce fertility and has side effects. Bodybuilding steroids can cause long-term hormone and fertility problems.
Common questions
When should testosterone be tested?
In men, early in the morning, ideally fasting, because levels are highest then.
What is a normal testosterone level in men?
Typically about 300–1000 ng/dL (about 10–35 nmol/L) in the morning. Always use the range printed on your report.
Does one low result mean low testosterone?
No. Low testosterone is diagnosed only when symptoms are present and morning levels are low on more than one test.
What causes high testosterone in women?
It is most often due to PCOS.