What Is a Quad Screen?

What to expect when undergoing this test

Midwife taking blood sample from arm of pregnant woman
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A quad marker test, also referred to as a quad-screen, is one of the tests you may have if you are pregnant. It is a blood test that can approximate the risk of problems that could affect your growing baby, such as Down syndrome, spina bifida, and miscarriage.

Purpose of Test

The quad test is recommended for all pregnant women during the early portion of the second trimester of pregnancy, between 15 to 20 weeks.

This test measures the levels of four different proteins and hormones, which is why it is called a quad test.

The levels checked are alpha-fetoprotein (AFP), human chorionic gonadotropin (HCG), estriol, and inhibin A. These hormones are produced during pregnancy, and the levels in your blood give your doctors useful information about the health of the baby, including the risk of certain birth defects.

  • AFP is a protein produced by the fetus, which is what the baby is called after 8 weeks of pregnancy.
  • HCG is a hormone produced by the placenta, which provides nourishment from the mother to the baby.
  • Estriol is a hormone produced by the placenta and the fetus.
  • Inhibin A is a hormone produced during pregnancy, and at other times as well.

The hormones can be produced in higher or lower than average amounts during pregnancy if the growing baby has Down syndrome, spina bifida, anencephaly, developmental problems, or a risk of miscarriage.

The levels can be detected in the mother’s blood, and abnormal amounts are used as markers of disease risk, but they cannot diagnose birth defects. Each genetic or developmental defect has its own definitive diagnostic tests.

Risks and Contraindications 

There are no medical risks, complications, or contraindications associated with this test.

It is a safe and easy blood test. However, some parents do not want to consider tests that could identify possible birth defects, for a variety of reasons, such as a concern that they may raise anxiety about the baby.

Before the Test

You do not need to do anything to physically prepare for the test. You should prepare yourself emotionally for the test by discussing the possible outcomes and their implications with your doctor and your child’s other parent ahead of time. 

Timing 

You may be able to have the test right away when your doctor orders it for you, or you might need to make an appointment to come back for the test. This depends on a number of factors, such as whether you have time to stay and get your blood drawn, and whether your doctor’s office or the hospital where you receive your prenatal care are ready to do the test for you.

Generally, a blood test should take about 10-15 minutes from when you are called in to meet the technician. 

Location

Your doctor’s office staff should be able to tell you where you can get your test done. It may be at your doctor’s office, a nearby lab, or at the hospital. Normally, your health insurance plan will have a list of several approved facilities where you can go to get your blood drawn.

What to Wear 

You can wear anything to get your blood drawn. Generally, it is best to wear either short-sleeves or loose sleeves that you can easily pull up above your elbows for easy access to the veins in your arm. If you are going to work afterward, you might want to wear long sleeves or a jacket over short sleeves so that you won’t have a visible bandage, if this matters to you.

Food and Drink

There are no special limitations as far as food and drink. Often, it is recommended that you eat or drink something before getting your blood drawn so that you won’t become dizzy or lightheaded afterward.

Cost and Health Insurance

In general, this test is likely to be covered by your health plan. Some health plans may require you to pay a copay, and there is also a possibility that your health plan won’t cover the cost at all. You should be able to get an answer regarding your coverage and the cost by calling the information number on your insurance card and giving them the name of the test.

If you are paying for the test yourself, the out-of-pocket cost can vary tremendously from region to region and even from one lab to another. There is likely a technician fee and a fee for processing. You can check the cost of the technician fee with your doctor’s office or hospital, and the cost of the processing fee with the lab where your test will be processed.

What to Bring

You should bring something to eat or drink for after the test to prevent yourself from feeling faint. You should also bring a jacket or a shawl, even if it is warm out, because some people feel cold after having blood drawn. 

You should also be sure to bring the order for your test, a form of identification, your insurance card, and a method of payment in case you have to pay a copay.

Other Considerations 

Before taking the quad screen test, you should be prepared for how you would handle the challenges of learning that your child could have one of the conditions that this test screens for. These diagnoses may mean that your growing baby could have a serious disease that could result in early death or physical or cognitive limitations that would require lifelong care. Remember, the quad test does not definitively diagnosis any condition your baby may have, rather, it might suggest that further testing should be done.

During the Test

You will probably not see your doctor during your test. You will see a phlebotomist, a technician who is specialized in drawing blood, or a nurse.

Pre-Test

Right before your blood test, you will need to check in. You will be asked to present your order form, your identification, and your method of payment. You may also be asked to sign some forms such as a consent form or a HIPPA patient privacy form, which acknowledges that the hospital, doctor, and lab are not permitted to share your medical information without your consent. 

After this sign in process is complete, you may be asked to wait until it is your turn to have your blood drawn. 

Throughout the Test

Once it is your turn to have the blood test, your nurse or phlebotomist will meet with you and confirm your identity. You will be asked to sit comfortably, probably with your arm on an armrest. Your phlebotomist will ask which hand you write with because it is often more comfortable if your blood is drawn from the non-dominant arm. 

You will have a band lightly tied around your arm, your phlebotomist will look at your veins, and will clean off the area. He or she will insert a needle into the vein, and you may feel a slight pinprick pain. The needle will remain in the vein for about 20 seconds as the blood enters into a tube for collection, and then the needle will be gently removed and a bandage placed over the small puncture wound. 

Post-Test 

After the test, your phlebotomist will make sure that you have stopped bleeding and may ask you to place your other hand over the wound for a few seconds to stop the bleeding. Once the bleeding stops, you will be discharged to leave.

After the Test 

After the test, it is a good idea to get something to eat or drink because some people feel slightly faint after getting blood drawn. You should be able to drive yourself home and you can resume your regular activities. 

Managing Side Effects 

Usually there are no side effects or complications after a quad test. The most common side effect is persistent bleeding or bruising. If you continue to soak bandages more than two hours after your blood is drawn, you should call your doctor.

Interpreting Results 

It may take approximately a week for your test results to be ready. The results of your quad screening test include numerical values of the four hormones that are tested. The test results will likely be sent to your doctor, and you may be able to look them up yourself on a computer if you have access to sign into your medical records.

The report itself may not include an assessment or comments about whether your baby is at high or low risk of certain conditions. Interpretation of these results requires a physician who is familiar with taking care of pregnant women.

The lab results and their meaning is as follows:

  • AFP: If your AFP is high in comparison to the normal range, then there is a chance that the growing baby has anencephaly or spina bifida. If AFP is low, this can be a marker of Down syndrome.
  • Estriol: Low levels of estriol can be a marker of Down syndrome, anencephaly and Edwards syndrome. 
  • HCG: Increased HCG levels are seen in Down syndrome and low levels are seen in anencephaly or Edwards syndrome.
  • Inhibin A: High levels of inhibin A are seen with Down syndrome.

It is important to note that these are only markers associated with an increased risk of these conditions and they are not the gold standard. High levels of HCG are also seen if you are pregnant with more than one baby, if you are further along in your pregnancy than you or your doctor initially estimated, or if you are taking medications.

According to the American College of Obstetrics and Gynecologists, the quad screen has an 80 percent chance of assessing the risk of Down syndrome, but the results of all four measures need to be evaluated to determine this estimate. Similarly, other conditions and risks need to be evaluated by considering more than one of the four measures. Using the quad screen test, there is a chance of overestimating or underestimating the risk of problems with the baby or the pregnancy.

Some of the conditions assessed by the quad screening test include:

  • Anencephaly is inadequate development of the brain. Spina bifida is a condition in which the spine does not form properly around the spinal cord. When the nervous system does not form properly, HCG, which is normally produced by the baby, can be present in excessive amounts. Anencephaly and spina bifida can be identified on an ultrasound test, which allows your doctor to visualize your growing baby in detail.
  • Down syndrome, also called trisomy 21, occurs when a baby has an extra chromosome 21. Children who have Down syndrome are able to survive well into adulthood, but may have heart defects and learning disabilities, as well as physical limitations. Down syndrome is diagnosed with a genetic test, usually an amniocentesis, which identifies the extra chromosome. 
  • Edwards syndrome, trisomy 18, another condition caused by an extra chromosome, causes defects of the bones and kidneys. Babies born with this condition do not survive for longer than a few days. Like Down syndrome, this condition can be defined with an amniocentesis.

Follow-Up

If you have an abnormal test result, the next diagnostic step is an ultrasound or a genetic test. However, these tests are optional and some parents choose not to proceed with them so they won’t have a negative expectation before the baby is born or for ethical or religious reasons. Other parents choose to know as much as possible in order to plan ahead, or to prepare for taking care of a baby with a disability.

A Word From Verywell 

If you are pregnant, there are certainly many questions that you have about your growing baby. Whether your baby will be healthy is one of the big questions.

A quad screen test is an easy procedure from a practical standpoint, but there are many emotional issues associated with this test result. Be sure to prepare yourself for the results by talking with your partner, your parents, your closest friend, or whoever you trust.

Your doctor may suggest that you meet with a genetic counselor either before or after the test results are ready. When you talk with professionals who have experience with these tests and the associated conditions, you will have the opportunity have all of your questions and concerns answered. Don’t hesitate to ask all of your questions and to discuss all of your options as you navigate your pregnancy.

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