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Estradiol (Blood)

Does this test have other names?


What is this test?

This test measures the amount of estradiol (E2), the form of estrogen made primarily by the ovaries.

E2 plays a key role in the female reproduction system. It's necessary for the development of the uterus, fallopian tubes, vagina, and breasts. Women have higher amounts of E2 during their reproductive years and almost none after menopause.

Other estrogens include estrone, which is the primary estrogen made during menopause, and estriol.

In men, E2 is secreted in moderate amounts by the testes throughout life. 

Why do I need this test?

You may need this test if your doctor suspects you have a problem caused by high or low levels of E2. These problems include:

  • Menstrual problems

  • Ovarian tumors

  • Gynecomastia, a noncancerous growth of the glandular breast tissue in males

  • Menopausal symptoms

  • Breast cancer

You may also have this test if you have assisted reproductive technology (ART) for infertility or your doctor is monitoring your hormones during ART.

In adolescents, this test may be done for early puberty.

What other tests might I have along with this test?

Your doctor may also order other tests, depending on what he or she suspects. These tests may include:

  • Follicle-stimulating hormone (FSH) and luteinizing hormone (LH), for menopausal problems and treatment

  • FSH, thyroid-stimulating hormone/free thyroxine (TSH/FT4), and prolactin, a hormone necessary for breast milk production, if your periods have stopped

  • FSH and LH, for early puberty

  • TSH, prolactin, FSH, and LH, for both male and female infertility issues

What do my test results mean?

Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.

Results are given in picograms per milliliter (pg/mL). Normal levels for estradiol are:

  • 30 to 400 pg/mL for premenopausal women

  • 0 to 30 pg/mL for postmenopausal women

  • 10 to 50 pg/mL for men

If your results are lower, it may mean you have ovarian failure, also called early menopause, or low estrogen from rapid weight loss or anorexia.

If your results are higher, it may mean you have tumors of the ovary, testes, or adrenal glands.

How is this test done?

The test requires a blood sample, which is drawn through a needle from a vein in your arm.

Does this test pose any risks?

Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.

What might affect my test results?

Taking birth control pills or hormone therapy may affect your results.

How do I get ready for this test?

You don't need to prepare for this test. But be sure your doctor 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.