An estradiol test measures the amount of a hormone called estradiol in the blood.
Estradiol is the most important form of estrogen found in the body. Most of it is made in and released from the ovaries, adrenal cortex, and the placenta, which forms during pregnancy to feed a developing baby.
Estradiol is responsible for the growth of the womb (uterus), Fallopian tubes, and vagina. It promotes breast development and the growth of the outer genitals. The hormone also plays a role in the distribution of body fat in women.
How the test is performed
A blood sample is needed. For information on how this is done, see: Venipuncture
How to prepare for the test
Certain medicines may interfere with test results, including:
- Estrogen therapy
- Birth control pills
How the test will feel
When the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.
Why the test is performed
This test may be done:
- To see how well your ovaries, placenta, or adrenal gland work
- If you have signs of an ovarian tumor
- If male or female body characteristics are not developing normally
- If your menstrual cycle (period) has stopped (levels of estradiol vary, depending on the time of month)
The test may also be used to monitor patients with hypopituitarism and women undergoing certain fertility treatments.
- Male: 10 to 50 picograms per milliliter (pg/mL)
- Female (premenopausal): 30 to 400 pg/mL
- Female (postmenopausal): 0 to 30 pg/mL
The examples above are common measurements for results of these tests. Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your doctor about the meaning of your specific test results.
What abnormal results mean
High levels of estradial may be a sign of an ovarian tumor.
Lower-than-normal levels may be due to:
- Turner syndrome
- Ovarian failure
- Low estrogen production related to rapid weight loss or low body fat
This list is not all-inclusive.
What the risks are
Veins and arteries vary in size from one patient to another and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight but may include:
- Excessive bleeding
- Fainting or feeling light-headed
- Hematoma (blood accumulating under the skin)
- Infection (a slight risk any time the skin is broken)
Webster RA. Reproductive function and pregnancy. In: McPherson RA, Pincus MR, eds. . 21st ed. Philadelphia, Pa: Saunders Elsevier; 2006:chap 25.
Ferri FF. Laboratory tests and interpretation of results. In: Ferri FF, ed. 1st ed. Philadelphia, Pa: Mosby Elsevier; 2011:section IV.