What is an estrogen test?
An estrogen test measures the level of estrogens in the blood or urine. Estrogen can also be measured in saliva using at-home test kit. Estrogens are a group of hormones that play a key role in the development of female physical features and reproductive functions, including the growth of breasts and the uterus, and regulation of the menstrual cycle. Men also make estrogen but in much smaller amounts.
There are many types of estrogens, but only three types are commonly tested:
- Estrone, also called E1, is the main female hormone made by women after menopause. Menopause is a time in a woman's life when her menstrual periods have stopped and she can't become pregnant anymore. It usually starts when a woman is around 50 years old.
- Estradiol, also called E2, is the main female hormone made by nonpregnant women.
- Estriol, also called E3 is a hormone that increases during pregnancy.
Measuring estrogen levels can provide important information about your fertility (the ability to get pregnant), the health of your pregnancy, your menstrual cycle, and other health conditions.
Other names: estradiol test, estrone (E1), estradiol (E2), estriol (E3), estrogenic hormone test
What is it used for?
Estradiol tests or estrone tests are used to help:
- Find out the reason for early or late puberty in girls
- Find out the reason for late puberty in boys
- Diagnose menstrual problems
- Find out the cause of infertility (the inability to get pregnant)
- Monitor infertility treatments
- Monitor treatments for menopause
- Find tumors that make estrogen
An estriol hormone test is used to:
Why do I need an estrogen test?
You may need an estradiol test or an estrone test if you:
- Are having trouble getting pregnant
- Are a woman of childbearing age who is not having periods or having abnormal periods
- Are a girl with early or delayed puberty
- Have symptoms of menopause, including hot flashes and/or night sweats
- Have vaginal bleeding after menopause
- Are a boy with delayed puberty
- Are a man showing female characteristics, such as the growth of breasts
If you are pregnant, your health care provider may order an estriol test between the 15th and 20th week of pregnancy as part of a prenatal test called a triple screen test. It can find out if your baby is at risk for a genetic birth defect such as Down syndrome. Not all pregnant women need to get an estriol test, but it is recommended for women who have a higher risk of having a baby with a birth defect. You may be at a higher risk if you:
What happens during an estrogen test?
Estrogens can be tested in blood, urine, or saliva. Blood or urine is usually tested in doctor's office or lab. Saliva tests can be done at home.
For a blood test:
A health care professional will take a blood sample from a vein in your arm, using a small needle.
After the needle is inserted, a small amount of blood will be collected into a test tube or vial. You may feel a little sting when the needle goes in or out. This usually takes less than five minutes.
For a urine test:
Your health care provider may ask you to collect all urine passed in a 24-hour period. This is called a 24-hour urine sample test. For this test, your health care provider or a laboratory professional will give you a container to collect your urine and instructions on how to collect and store your samples. A 24-hour urine sample test generally includes the following steps:
- Empty your bladder in the morning and flush that urine down. Do not collect this urine. Record the time.
- For the next 24 hours, save all your urine passed in the container provided.
- Store your urine container in the refrigerator or a cooler with ice.
- Return the sample container to your health provider's office or the laboratory as instructed.
For an at-home saliva test, talk your health care provider. He or she can tell you which kit to use and how to prepare and collect your sample.
Will I need to do anything to prepare for the test?
You don't need any special preparations for an estrogen test.
Are there any risks to the test?
There is very little risk to having a blood test. You may have slight pain or bruising at the spot where the needle was put in, but most symptoms go away quickly.
There is no known risk to a urine or saliva test.
What do the results mean?
If your estradiol or estrone levels are higher than normal, it may be due to:
- A tumor of the ovaries, adrenal glands, or testicles
- Early puberty in girls; delayed puberty in boys
If your estradiol or estrone levels are lower than normal, it may be due to:
- Primary ovarian insufficiency, a condition that causes a woman's ovaries to stop working before she is 40 years old
- Turner syndrome, a condition in which a woman's sexual characteristics don't develop properly
- An eating disorder, such as anorexia nervosa
- Polycystic ovary syndrome, a common hormone disorder affecting childbearing women. It is one of the leading causes of female infertility.
If you are pregnant and your estriol levels are lower than normal, it may mean your pregnancy is failing or that there is a chance your baby might have a birth defect. If the test shows a possible birth defect, you will need more testing before a diagnosis can be made.
Higher levels of estriol may mean you will be going into labor soon. Normally, estriol levels go up about four weeks before you start labor.
If you have questions about your results, talk to your health care provider.
Learn more about laboratory tests, reference ranges, and understanding results.
- American Pregnancy Association [Internet]. Irving (TX): American Pregnancy Association; c2018. Triple Screen Test; [updated 2019 Oct 5; cited 2020 May 9]; [about 3 screens]. Available from: http://americanpregnancy.org/prenatal-testing/triple-screen-test
- ClinLab Navigator [Internet]. ClinLab Navigator; c2018. Estradiol; [cited 2020 May 9]; [about 2 screens]. Available from: http://www.clinlabnavigator.com/estradiol.html
- Johns Hopkins Medicine [Internet]. Johns Hopkins Medicine; Health Library: Glossary: Estrogen’s Effects on the Female Body; [cited 2020 May 9]; [about 3 screens]. Available from: https://www.hopkinsmedicine.org/health/conditions-and-diseases/estrogens-effects-on-the-female-body
- Hinkle J, Cheever K. Brunner & Suddarth’s Handbook of Laboratory and Diagnostic Tests. 2nd Ed, Kindle. Philadelphia: Wolters Kluwer Health, Lippincott Williams & Wilkins; c2014. Estrogens (Serum) (E1); p. 275-76.
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- Lab Tests Online [Internet]. Washington D.C.: American Association for Clinical Chemistry; c2001-2018. 24-Hour Urine Sample; [updated 2017 Jul 10; cited 2020 May 9]; [about 3 screens]. Available from: https://labtestsonline.org/glossary/urine-24
- Mayo Clinic: Mayo Medical Laboratories [Internet]. Mayo Foundation for Medical Education and Research; c1995–2018. Test ID: UE3: Estriol, Unconjugated, Serum: Clinical and Interpretive; [cited 2018 May 9]; [about 4 screens]. Available from: https://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/81711
- National Heart, Lung, and Blood Institute [Internet]. Bethesda (MD): U.S. Department of Health and Human Services; Blood Tests; [cited 2020 May 9]; [about 3 screens]. Available from: https://www.nhlbi.nih.gov/health-topics/blood-tests
- University of Rochester Medical Center [Internet]. Rochester (NY): University of Rochester Medical Center; c2018. Health Encyclopedia: Estradiol (Blood); [cited 2020 May 9]; [about 2 screens]. Available from: https://www.urmc.rochester.edu/encyclopedia/content.aspx?ContentTypeID=167&ContentID=estradiol
- UW Health [Internet]. Madison (WI): University of Wisconsin Hospitals and Clinics Authority; c2018. Health Information: Estrogens: Results [updated 2019 Dec 7; cited 2020 May 9]; [about 9 screens]. Available from: https://www.uwhealth.org/health/topic/medicaltest/estrogen-test/hw6200.html#hw6209
- UW Health [Internet]. Madison (WI): University of Wisconsin Hospitals and Clinics Authority; c2018. Health Information: Estrogens: Test Overview; [updated 2019 Dec 7; cited 2020 May 9]; [about 2 screens]. Available from: https://www.uwhealth.org/health/topic/medicaltest/estrogen-test/hw6200.html#hw6203 UW Health [Internet]. Madison (WI): University of Wisconsin Hospitals and Clinics Authority; c2018. Health Information: Estrogens: Why It is Done; [updated 2019 Dec 7; cited 2020 May 9]; [about 4 screens]. Available from: https://www.uwhealth.org/health/topic/medicaltest/estrogen-test/hw6200.html#hw6204