This test measures the amount of estradiol (E2), the form of estrogen made mainly 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 and estriol. Estrone is the main estrogen made during menopause.
In men, E2 is secreted in moderate amounts by the testes throughout life.
You may need this test if your healthcare provider thinks you have a problem caused by high or low levels of E2. These problems include:
Gynecomastia, a noncancerous growth of the glandular breast tissue in males
You may also have this test if you have assisted reproductive technology (ART) for infertility. Or you may have the test if your healthcare provider is monitoring your hormones during ART.
In adolescents, this test may be done for early puberty.
Your healthcare provider 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 needed for breastmilk production, if your periods have stopped
FSH and LH, for early puberty
TSH, prolactin, FSH, and LH, for both male and female infertility issues
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.
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.
The test is done with a blood sample. A needle is used to draw blood from a vein in your arm or hand.
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.
Taking birth control pills or hormone therapy may affect your results.
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.