Estrogens
Test OverviewAn estrogen test measures the level of the most
important estrogen
hormones in a blood
or urine sample. It measures estradiol, estriol, and estrone. - Estradiol is the most common type of
estrogen measured for nonpregnant women. The amount of estradiol in a woman's blood
varies throughout her
menstrual cycle. After
menopause, it drops to a very low
but constant level.
- Estriol levels are most often measured only during
pregnancy. Estriol is produced in large amounts by the
placenta. This is the tissue that links the fetus to the
mother. Estriol can be found as early as the 9th week of pregnancy. The levels keep rising until delivery. Estriol can also be measured in
urine.
- Estrone may be measured in women who have gone through
menopause. It's done to find out their estrogen levels. It also may be measured in men or
women who might have cancer of the
ovaries,
testicles, or
adrenal glands.
Both men and women make estrogen hormones. Estrogens are
responsible for female sexual development and function, such as breast
development and the menstrual cycle. In women, estrogens are made mainly in
the ovaries and in the placenta during pregnancy. Small amounts are also made by the adrenal glands. In men, small amounts of estrogens are made
by the adrenal glands and testicles. Small amounts of estrone are made
throughout the body in most tissues, especially fat and muscle. This is the
major source of estrogen in women who have gone through menopause. For pregnant women, the level of estriol in the blood is used in a
maternal serum triple or quadruple screening test.
In most cases, these tests are done between 15 and 20 weeks of pregnancy. They check the levels of three
or four substances in a pregnant woman's blood. The triple screen checks
alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and a type of
estrogen (unconjugated estriol, or uE3). The quad screen checks these
substances and the level of the hormone inhibin A. The levels of these
substances-along with a woman's age and other factors-help the doctor figure out
the chance that the baby may have certain problems or birth defects. - Pregnancy: Should I Have Screening Tests for Birth Defects?
Why It Is DoneA test for estrogen is done to: - Help find fetal birth defects (especially
Down syndrome) during pregnancy. When the test for
estriol is done with alpha-fetoprotein (AFP) and human chorionic
gonadotropin (hCG), it is called a triple screen test. When the amount of a
hormone called inhibin A is also measured along with estriol, AFP, and hCG, the
test is called a quad marker screen. Other blood tests and fetal ultrasound may
be done as well.
- Check for estrogen-producing tumors of the ovaries
in girls before menstruation starts and in women after
menopause.
- Explain abnormal sexual traits in men, such as
enlarged breasts (gynecomastia). This test can also help find out if there are
estrogen-producing tumors growing in the testicles.
- Monitor treatment
with fertility medicines.
How To PrepareYou do not need to do anything special to prepare for this test. Tell your doctor if
you: - Are menstruating. Note where you are in your
menstrual cycle.
- Are using birth control pills, patches, rings, or other forms
of hormonal birth control.
- Are or might be pregnant.
Talk to your doctor if you have any concerns about the need for the test, its risks, how it will be done, or what the results will mean. To help you understand the importance of this test,
fill out the
medical test information form(What is a PDF document?). How It Is DoneThe health professional taking a sample of your blood will: - Wrap an elastic band around your upper arm to
stop the flow of blood. This makes the veins below the band larger so it is
easier to put a needle into the vein.
- Clean the needle site with
alcohol.
- Put the needle into the vein. More than one needle stick
may be needed.
- Attach a tube to the needle to fill it with
blood.
- Remove the band from your arm when enough blood is
collected.
- Put a gauze pad or cotton ball over the needle site as
the needle is removed.
- Put pressure on the site and then put on a
bandage.
How It FeelsYou may feel nothing at all from the
needle, or you may feel a quick sting or pinch. Some people feel a stinging pain while the needle is in the
vein. But many people feel little or no pain after the needle is in the vein. RisksThere is very little chance of a problem from
having a blood sample taken from a vein. - You may get a small bruise at the site. You can lower the chance of bruising by keeping pressure on the site for
several minutes.
- In rare cases, the
vein may become swollen after the blood sample is taken. This problem is
called phlebitis. You can use a warm compress several
times a day to treat this.
ResultsAn estrogen test measures the level of the
most important estrogen
hormones (estradiol, estriol, and estrone) in a blood
or urine sample. Results are usually available within 24
hours. NormalFor girls and women between puberty and
menopause, estrogen levels vary throughout the
menstrual cycle. These numbers are just a guide. The range for "normal" varies from lab to lab. Your lab may have a different range. Your lab report should show what range your lab uses for "normal." Also, your doctor will evaluate your results based on your health and other factors. So a number that is outside the normal range here may still be normal for you.
Many conditions can change
estrogen levels. Your doctor will talk with you about any important abnormal
results as they relate to your symptoms and past health. High valuesHigh values may be caused by: Low valuesLow values may be caused by: - Problems with ovarian function. This can be
caused by a failure of an ovary to develop properly (Turner's syndrome) or because of a drop in
pituitary gland activity.
- Anorexia nervosa.
- Menopause.
- A
problem with the fetus or placenta during pregnancy.
What Affects the TestYou may not be able to have the test, or the results may not be helpful, if: - You use hormone therapy after menopause.
- You use birth control pills, patches, or
rings and other forms of hormonal birth control.
- Within 1 week before your test, you had a test that
uses a radioactive substance, such as a
bone scan.
- You use certain medicines, such as clomiphene or steroids
(for example, prednisone).
- You have high levels of sugar in your urine caused
by
diabetes.
What To Think About- A blood test works better than a urine test to see how well the ovaries are working.
- Tests that measure blood levels of progesterone,
luteinizing hormone, and follicle-stimulating hormone are often used to study
the problems that can affect fertility and the menstrual cycle.
- In some cases, screening tests are done in the first trimester of pregnancy to look for
Down syndrome. The first trimester screening is often an ultrasound that measures the thickness of skin at the back of the fetus's neck (nuchal
translucency). It also includes a blood test for the pregnancy hormone hCG and a protein called pregnancy-associated
plasma protein A. To learn more, see the topic
Birth Defects Testing.
- The level of estriol in the blood is often used in a
maternal serum triple or quadruple screening test. To learn more, see the topic Triple or Quad Screening for Birth Defects.
ReferencesCitations- Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
Other Works Consulted- Fischbach FT, Dunning MB III, eds. (2009). Manual of Laboratory and Diagnostic Tests, 8th ed. Philadelphia: Lippincott Williams and Wilkins.
- Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier.
- Wapner RJ, et al. (2009). Prenatal diagnosis of congenital disorders. In RK Creasy et al., eds., Creasy and Resnik's Maternal-Fetal Medicine: Principles and Practice, 6th ed., pp. 221-274. Philadelphia: Saunders Elsevier.
CreditsByHealthwise Staff Primary Medical ReviewerSarah Marshall, MD - Family Medicine Martin J. Gabica, MD - Family Medicine E. Gregory Thompson, MD - Internal Medicine Specialist Medical ReviewerSiobhan M. Dolan, MD, MPH - Reproductive Genetics Current as ofOctober 13, 2016 Current as of:
October 13, 2016 Chernecky CC, Berger BJ (2008). Laboratory Tests and Diagnostic Procedures, 5th ed. St. Louis: Saunders. Pagana KD, Pagana TJ (2010). Mosby's Manual of Diagnostic and Laboratory Tests, 4th ed. St. Louis: Mosby Elsevier. Last modified on: 8 September 2017
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