Sex Hormone Binding Globulin (Blood)
Does this test have other names?
SHBG blood test
What is this test?
This test measures the level of sex hormone binding globulin (SHBG) in your blood.
SHBG is a protein made by your liver. It binds tightly to three sex hormones found
in both men and women. These hormones are estrogen; dihydrotestosterone (DHT), and
testosterone. SHBG carries these three hormones throughout your blood.
Although SHBG binds three hormones, the hormone that's critical in this test is testosterone.
SHBG controls the amount of testosterone that your body tissues can use. Too little
testosterone in men and too much testosterone in women can cause problems. The level
of SHBG in your blood changes because of factors such as sex and age. It can also
change because of obesity, liver disease, and hyperthyroidism.
Why do I need this test?
You may need this test if your healthcare provider suspects that you have abnormal
testosterone levels. The test can help diagnose various conditions and diseases, including:
Androgen deficiency. Low levels of the hormone androgen can cause general weakness and sexual problems
in men. In women, androgen may affect thinking and bone strength. It may also prevent
the ovaries from working the way they should.
Hypogonadism. This condition happens mostly in men. It is found in men with low testosterone and
low sperm production.
What other tests might I have along with this test?
Your healthcare provider will likely also order total and free testosterone blood
levels. This is because SHBG levels tend to change. Both the SHBG and total testosterone
tests are needed to confirm an androgen deficiency.
What do my test results mean?
Test results may vary depending on your age, gender, health history, the method used
for the test, and other things. Your test results may not mean you have a problem.
Ask your healthcare provider what your test results mean for you.
Low levels of SHBG can be related to:
High levels of SHBG can be related to:
How is this test done?
The test is done with a blood sample. A needle is used to draw blood from a vein in
your arm or hand.
Does this test pose any risks?
Having a blood test with a needle carries some risks. These include bleeding, infection,
bruising, and feeling lightheaded. When the needle pricks your arm or hand, you may
feel a slight sting or pain. Afterward, the site may be sore.
What might affect my test results?
Pain killers called opiates, medicines for the central nervous system, and recreational
drugs can all affect your test results. Having an eating disorder or engaging in excessive,
strenuous exercise can also affect your results.
How do I get ready for this test?
You don't need to prepare for this test. Be sure your healthcare provider knows about
all medicines, herbs, vitamins, and supplements you are taking. This includes medicines
that don't need a prescription and any illicit drugs you may use.