Patient education: Testosterone test (The Basics)

What is a testosterone test? — 

This measures the amount of testosterone in the blood. Testosterone is the most important "male hormone," or "androgen."

The amount of testosterone a person "normally" has depends on several things, including:

●Birth-recorded sex – This is a person's sex when they are born, based on their body's biology. Everyone makes testosterone, but the level of testosterone in a male's blood is much higher than in a female's.

●Age – In males, the level of testosterone rises as the body begins to go through puberty.

Most people get a "total" testosterone test, which measures all forms of testosterone in the body. There is also a "free" testosterone test, but doctors do not use it often.

Why might I get a testosterone test? — 

It depends on your birth-assigned sex.

For males, doctors might order a testosterone test to:

●Learn more about early or late puberty – For example, if a child has signs of early puberty or if a teen has not gone through puberty at the expected time, a testosterone test and other tests can give more information.

●Check for causes of infertility – In males, this means trouble getting a partner pregnant. This can happen for different reasons. For example, a testosterone test can help the doctor figure out why you have too few sperm.

●Figure out the cause of sexual problems – These might include trouble getting or keeping an erection, or having little or no interest in sex (called "low libido").

●Check for certain conditions – For example, a testosterone test can help the doctor figure out if you have "hypogonadism." This is when your testosterone level is too low and causes symptoms, such as sexual problems or feeling tired, sad, down, or depressed.

●Check if certain treatments are working – For example:

•If your doctor prescribes testosterone because your body is not making enough, a blood test can help them figure out if you are getting the right amount.

•If you have prostate cancer, you might get "androgen deprivation therapy," which can lower your testosterone level. A testosterone test can help the doctor figure out if the treatment is working.

For females, doctors might order a testosterone test to:

●Figure out the cause of symptoms like irregular periods, excess body hair, and acne – These can be a sign testosterone levels are higher than normal.

●Check for causes of infertility – In females, this means trouble getting pregnant. This can happen for different reasons. If you are having trouble getting pregnant and also have excess body hair, your doctor might order a testosterone test to check for a condition called "polycystic ovarian syndrome," or "PCOS."

●Check for or monitor certain kinds of tumors that produce testosterone

If you take testosterone for gender-affirming care, a testosterone test can help the doctor decide if you are getting the right amount.

How do I prepare for a testosterone test? — 

You need to get a "blood draw." For males, the test is done between 8 and 10 AM. For females, it can be done at any time.

Your doctor will give you instructions about eating or drinking before the test. Males usually need to avoid eating or drinking anything besides water for 8 to 12 hours before the test. Females usually do not need to do this.

It might help to wear a short-sleeve shirt to your blood draw appointment. This makes it easier for the person drawing your blood to get to your arm.

What happens during a blood draw? — 

A needle is used to take a small amount of blood from your arm (figure 1). Collecting the blood only takes a few minutes. The blood is then tested in a lab.

Tell the person who takes your blood:

●If you take "blood thinner" medicines or have a bleeding problem – They will make sure your bleeding is under control before you leave.

●If you have a latex allergy – Some of the supplies used for blood draws might contain latex.

●If you have a preferred arm to use

Most of the time, getting blood taken does not cause problems. You might have a little soreness or bruising where the needle went in.

What do my results mean? — 

Your doctor or nurse will tell you when to expect your results, and will contact you with the results. Or if you use an online "patient portal," you might get an alert there when your results are ready.

If your testosterone test shows any abnormal results, your doctor or nurse will talk to you about what to do next. They might need to do more tests to figure out the cause.

Your doctor also might need to repeat the testosterone test several times.

If you have a health problem, your doctor will work with you to come up with a treatment plan.

More on this topic

Patient education: Low testosterone in males (The Basics)
Patient education: Androgen replacement in men (The Basics)
Patient education: Early puberty (The Basics)
Patient education: Late puberty (The Basics)
Patient education: Male infertility (The Basics)
Patient education: Female infertility (The Basics)
Patient education: Sex problems in males (The Basics)
Patient education: Absent or irregular periods (The Basics)
Patient education: Hirsutism (excess hair growth in women) (The Basics)
Patient education: Polycystic ovary syndrome (The Basics)
Patient education: Being transgender (The Basics)
Patient education: Gynecomastia (male breast development) (The Basics)

Patient education: Evaluation of infertility in couples (Beyond the Basics)
Patient education: Treatment of male infertility (Beyond the Basics)
Patient education: Sexual problems in males (Beyond the Basics)
Patient education: Absent or irregular periods (Beyond the Basics)
Patient education: Hirsutism (excess hair growth in females) (Beyond the Basics)
Patient education: Polycystic ovary syndrome (PCOS) (Beyond the Basics)
Patient education: Gynecomastia (breast enlargement in males) (Beyond the Basics)