Estriol Test

The Estriol Test test contains 1 test with 1 biomarker .

Brief Description: The Estriol test measures the level of estriol, a type of estrogen, in the blood or urine. Estriol is primarily produced by the placenta during pregnancy and plays a crucial role in fetal development and maintaining a healthy pregnancy. The test helps assess the level of estriol and provides important information about fetal well-being and potential pregnancy complications.

Also Known As: Estriol LCMSMS Serum, Estriol Blood Test, Oestriol Test, E3 Test

Collection Method: Blood Draw 
Specimen Type: Serum 

Test Preparation: No preparation required

When is an Estriol test ordered?

An Estriol test may be ordered during pregnancy, typically between weeks 15 and 22, as part of the maternal serum screening or prenatal care. It is commonly performed in the following situations:

1. Prenatal Screening: The Estriol test is often included in the triple or quadruple screening test, which evaluates the risk of certain fetal chromosomal abnormalities, such as Down syndrome. Estriol, along with other markers, helps assess the overall risk and provides information for further diagnostic testing if needed.

2. Assessment of Fetal Well-Being: The Estriol test can help assess the well-being and development of the fetus. Low levels of estriol may indicate potential issues with fetal growth, placental function, or fetal adrenal gland disorders.

3. Monitoring High-Risk Pregnancies: In high-risk pregnancies, such as those with a history of fetal growth restriction, preeclampsia, or gestational diabetes, regular Estriol testing may be ordered to monitor fetal health and identify any complications that may require intervention.

What does an Estriol blood test check for?

Estrogens are a class of steroids that have a role in the development and operation of female reproductive organs, as well as the generation of secondary sex characteristics. They help regulate the menstrual cycle, are involved in the growth of breasts and the uterus, and aid in the maintenance of a healthy pregnancy, together with another hormone, progesterone. Though they are primarily associated with women, they are also prevalent in men and play a role in bone metabolism and growth in both genders. Estrogen tests look for one of three hormones in the blood: estrone, estradiol, or estriol.

The placenta produces estriol, which increases in concentration throughout a woman's pregnancy. Increasing levels indicate that the pregnancy and the developing infant are in good health. Estriol is part of the maternal serum screen, which is done in the second trimester to assess fetal risk owing to chromosomal abnormalities. Non-pregnant women and males have very low amounts of E3.

During pregnancy, the predominant estrogen is estriol. The placenta produces it, and it begins to rise in the eighth week of pregnancy and continues to rise throughout the pregnancy. Approximately 4 weeks previous to the start of labor, the level of E3 rises dramatically. Estriol, which circulates in maternal blood, is soon excreted. Each test of estriol is a snapshot of what is going on with the placenta and fetus, yet estriol concentrations vary naturally during the day.

E3 levels are virtually undetectable after delivery.

Lab tests often ordered with an Estriol test:

When an Estriol test is ordered, it's typically part of a broader evaluation of fetal health and pregnancy monitoring. Here are some tests commonly ordered alongside it:

1. Alpha-fetoprotein (AFP) Test:

   • Purpose: To measure the level of AFP, a protein produced by the fetal liver.
   • Why Is It Ordered: Elevated or decreased AFP levels can indicate certain birth defects, including neural tube defects and abdominal wall defects. AFP testing is a standard component of the triple or quad screen in pregnancy.

2. Human Chorionic Gonadotropin (hCG) Test:

   • Purpose: To measure the level of hCG, a hormone produced by the placenta.
   • Why Is It Ordered: Part of the triple or quad screen; abnormal levels can indicate potential issues with the pregnancy, including chromosomal abnormalities.

3. Inhibin A Test:

   • Purpose: To measure levels of inhibin A, a hormone produced by the placenta and ovaries.
   • Why Is It Ordered: Inhibin A is included in the quad screen and can help assess the risk of Down syndrome and other chromosomal abnormalities.

4. Complete Blood Count (CBC):

   • Purpose: Provides a broad picture of overall blood health.
   • Why Is It Ordered: To monitor the health of the pregnant individual, including checking for anemia, which is common during pregnancy.

5. Glucose Screening Tests:

   • Purpose: To screen for gestational diabetes.
   • Why Is It Ordered: Gestational diabetes can impact both the pregnant individual and the fetus and needs to be managed appropriately.

6. Blood Type and Rh Factor:

   • Purpose: To determine the blood type and Rh status.
   • Why Is It Ordered: To identify potential Rh incompatibility between the pregnant individual and the fetus, which can lead to complications.

These tests, when ordered alongside an Estriol test, provide a comprehensive view of the health of the pregnancy and the developing fetus. They are important for assessing the risk of birth defects, monitoring the progress of the pregnancy, and ensuring the well-being of both the pregnant individual and the fetus. The specific combination of tests will depend on the individual's health history, the stage of pregnancy, and any symptoms or concerns that arise during prenatal care.

Conditions where an Estriol test is recommended:

An Estriol test may be required in the following conditions or diseases:

1. Pregnancy Monitoring: Estriol testing is routinely performed during pregnancy to monitor fetal well-being, assess placental function, and identify potential complications.

2. Evaluation of Fetal Chromosomal Abnormalities: Estriol testing is an important component of prenatal screening for chromosomal abnormalities, such as Down syndrome, Edwards syndrome, or Patau syndrome. Abnormal levels of estriol may indicate an increased risk of these conditions.

3. Evaluation of Fetal Growth: In cases of suspected fetal growth restriction or other issues related to fetal development, an Estriol test may be ordered to assess the adequacy of placental function and fetal well-being.

How does my health care provider use an Estriol test?

Health care providers use the results of an Estriol test in the following ways:

1. Risk Assessment: Estriol levels, along with other markers, help calculate the risk of certain fetal abnormalities, such as chromosomal abnormalities or neural tube defects. The results guide further diagnostic testing or provide reassurance if the risk is low.

2. Monitoring of Fetal Well-Being: Serial Estriol testing throughout pregnancy helps monitor placental function, fetal growth, and overall fetal well-being. Abnormal levels may indicate the need for additional interventions or monitoring.

3. Decision-Making and Patient Counseling: The results of the Estriol test assist health care providers in making informed decisions regarding the management of high-risk pregnancies. They also facilitate counseling and discussions with expectant parents about potential risks and available options.

It's important to note that the interpretation of Estriol test results should take into account the gestational age, individual patient factors, and the context of other prenatal screening results. Any abnormal findings require further evaluation and discussion with a qualified health care professional specializing in prenatal care.

What do my Estriol test results mean?

The sex and age of the person being tested determine the normal estrogen levels. It also depends on a woman's menstrual cycle or whether she is pregnant.

Estrogen levels can be elevated or lowered in a variety of metabolic disorders. Because the levels of estrone, estradiol, and estriol change from day to day and throughout a woman's menstrual cycle, care must be used when interpreting the results.

Rather than examining single numbers, a health practitioner monitoring a woman's hormones will look at trends in the levels, rising or falling over time in connection with the menstrual cycle or pregnancy. The findings of a test are not diagnostic of a specific ailment, but they do provide information to a health care provider regarding the possible source of a person's symptoms or status.

Most Common Questions About the Estriol test:

Understanding the Estriol Test

What is the Estriol test?

The Estriol test is a blood test that measures the levels of estriol, a type of estrogen produced primarily during pregnancy. It's often part of a maternal serum triple or quadruple screening test to assess the risk of certain birth defects.

Why would an Estriol test be performed?

The Estriol test is commonly done as part of routine prenatal screening during the second trimester of pregnancy. It helps evaluate the risk of the baby having certain chromosomal abnormalities, like Down syndrome, and neural tube defects.

Interpreting Estriol Test Results

What does a low Estriol test result mean?

Low levels of estriol in a pregnant woman's blood might suggest that the baby could have certain chromosomal abnormalities, such as Down syndrome, or a neural tube defect. However, a low result doesn't necessarily mean that the baby has these conditions, but further diagnostic tests would be recommended.

What does a high Estriol test result mean?

High levels of estriol are generally considered normal during pregnancy. However, extremely high levels may indicate a molar pregnancy or multiple pregnancies (twins, triplets, etc.). It's important to understand that the interpretation of estriol levels is complex and needs to be evaluated along with other factors and tests.

Estriol Test and Pregnancy

Can the Estriol test predict the gender of my baby?

No, the Estriol test cannot predict the gender of the baby. It is used to assess the risk of certain birth defects and is not related to the baby's sex.

Can the Estriol test be used to monitor the progress of my pregnancy?

While the Estriol test isn't typically used to monitor the entire progress of a pregnancy, its levels can provide information about the baby's development, particularly the health of the placenta and the baby's adrenal gland.

How does the Estriol test fit into the triple or quadruple screen during pregnancy?

In the triple or quadruple screen, the Estriol test is combined with tests for alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and possibly inhibin A. These tests together assess the risk of certain chromosomal abnormalities and neural tube defects in the baby.

Why might my healthcare provider repeat the Estriol test during my pregnancy?

If your initial Estriol test result was abnormal, your healthcare provider might recommend a repeat test or additional testing to confirm the results and gather more information about potential risks to your baby.

General Queries

What can affect the accuracy of an Estriol test?

Several factors can affect the accuracy of an Estriol test. Incorrect gestational age can lead to misinterpretation of results since estriol levels change throughout pregnancy. Certain medical conditions in the mother, like liver or kidney disease, can also impact estriol levels.

Can men or non-pregnant women have an Estriol test?

While estriol is found in all genders, the levels are much higher in pregnant women. The Estriol test is usually only ordered for pregnant women as part of prenatal screening.

Can the Estriol test detect a molar or ectopic pregnancy?

Abnormally high estriol levels can indicate a molar pregnancy, where a non-viable fertilized egg implants in the uterus. However, an ectopic pregnancy doesn't typically raise estriol levels because it occurs outside the uterus and the placenta (which produces estriol) does not develop properly.

Can the Estriol test detect neural tube defects like spina bifida?

Yes, the Estriol test, particularly when used in combination with other tests like AFP in the triple or quadruple screen, can help identify an increased risk of neural tube defects like spina bifida in the baby.

How can I prepare for an Estriol test?

There's no special preparation needed for an Estriol test. You should inform your healthcare provider about any medications you're taking as some can affect estriol levels.

Can an Estriol test indicate if I'm at risk for preterm labor?

Research has suggested that low levels of estriol in saliva or blood might be associated with an increased risk of preterm labor. However, more research is needed, and currently, the estriol test is not routinely used for this purpose.

Can the Estriol test indicate the health of the placenta?

Yes, estriol is produced by the placenta, and its levels can provide information about the placenta's health. Low levels of estriol may suggest potential issues with the placenta.

What should I do if my Estriol test result is abnormal?

If your Estriol test result is abnormal, your healthcare provider will likely recommend further testing to gather more information. This may include ultrasound scans or more invasive procedures like amniocentesis.

What are the risks associated with an abnormal Estriol test result?

An abnormal Estriol test result doesn't necessarily mean there's a problem with your pregnancy. It simply means that there may be a higher risk for certain conditions, and further testing is required to make a definitive diagnosis.

How does the Estriol test differ from other hormone tests during pregnancy?

The Estriol test specifically measures the level of estriol, a type of estrogen produced primarily by the placenta. It's used as part of the triple or quadruple screening to assess the risk of certain birth defects. Other hormone tests, such as those measuring hCG or progesterone, have different purposes and provide different information about the pregnancy.

Can the Estriol test be used in conjunction with other tests to provide a more comprehensive understanding of my baby’s health?

Yes, the Estriol test is often used together with other tests, such as AFP, hCG, and inhibin A in the triple or quadruple screen, to provide a more comprehensive picture of the baby's risk for certain birth defects.

What is the relationship between Estriol levels and Down Syndrome risk?

Low levels of estriol, along with abnormal levels of other hormones tested in the triple or quadruple screen, can indicate an increased risk of the baby having Down syndrome.

What are the typical Estriol levels throughout pregnancy?

Estriol levels increase gradually during pregnancy, peaking just before birth. Normal levels vary widely, which is why it's important for results to be interpreted by a healthcare provider familiar with your overall health and the specifics of your pregnancy.

How is the Estriol test result interpreted with respect to gestational age?

Estriol levels change throughout pregnancy, so it's important that the gestational age is accurate for the most meaningful interpretation of the test result. Levels are typically quite low early in pregnancy and increase as the pregnancy progresses.

Can the Estriol test determine if I'm having twins or triplets?

Estriol levels may be higher in multiple pregnancies because more placental tissue produces more estriol. However, this test is not specifically used to diagnose multiple pregnancies. Other tests and imaging techniques like ultrasounds are more reliable for that purpose.

Is the Estriol test effective in pregnancies achieved through IVF or other fertility treatments?

Yes, the Estriol test can be effectively used in pregnancies achieved through IVF or other fertility treatments. However, the interpretation of results might be slightly different in such cases, particularly if donor eggs were used or if the woman is of advanced maternal age. It's important to discuss the specifics of your situation with your healthcare provider.

We advise having your results reviewed by a licensed medical healthcare professional for proper interpretation of your results.