If you’re pregnant or planning on becoming pregnant, you are probably considering the various medical aspects of this exciting time. Ultrasounds give you an image you can hold as you imagine meeting your baby face to face. Monthly measurements of your expanding abdomen mark the growing anticipation as well. However, some medical procedures and visits with your doctor don’t always give you the reassurance for which you are looking. Tests like the quad screen are optional screening measures that some pregnant women choose to complete during pregnancy, based on risk factors that she and her physician decide might warrant the test. If you are considering the quad screen, there are many things you need to consider.
Multiple Marker Screening – What does it look for during pregnancy?
The quad screen is also referred to by several other names, including the quadruple marker test, multiple marker screening, AFP plus, Triple screen test, AFP maternal, MSAFP, and 4-marker screen. This prenatal test is used to measure the levels of four specific substances that appear in your blood during pregnancy.
- Alpha-fetoprotein (AFP) – this protein is made by your growing baby
- Human chorionic gonadotropin (HCG) – this is a hormone that is made by the placenta (the organ that connects your baby to you – and helps nourish and maintain your baby)
- Estriol – this hormone is produced by both the placenta and your baby’s liver
- Inhibin A – this is a hormone that your placenta produces
The quad screen is usually done sometime between your 15th and 20th weeks of pregnancy (the second trimester), if you and your doctor decide that it is an appropriate screening tool for your pregnancy. The test is relatively simple and does not put your growing baby at risk. The only complications that might result from this blood draw are bruising at the site of the blood draw or the risk of fainting if you are uncomfortable with needle testing. The pain associated with the testing is minimal and no different from any other blood draw tests.
The results of the quad screen could indicate one of several complications for your baby:
- Trisomy 21 (Down Syndrome) – This genetic condition causes developmental problems for your baby’s mental and social growth, and can also detrimentally affect your baby’s physical health with things such as heart defects.
- Trisomy 18 (Edwards Syndrome) – This genetic condition is often fatal by the time an infant reaches his first birthday as the result of severe developmental delays.
- Spina Bifida – This is a neural tube birth defect that results in the tissue that surrounds your baby’s spinal cord closing improperly, resulting in rather severe physical and/or mental impairments.
- Anencephaly – This condition refers to the malformation and underdevelopment of your baby’s skull and brain. Babies born with anencephaly rarely survive for more than a few hours after birth, if at all.
If your test results show that there are abnormally high levels of the specific markers, it indicates that there is an increased risk that your baby has a chromosomal or neural tube problem, but it doesn’t specify which one or to what extent.
Why should I have the quad screen?
Not all patients (and not all physicians) feel the same way about the quad screen. This optional test can only indicate to you and your health care provider if you are at an increased risk of carrying a child with one of the mentioned conditions, but it can’t actually tell you with certainty of the health of your unborn child.
A combination of your age, family history of these birth defects, overall health, and complications during previous pregnancies will help determine if you might be at a higher risk for these conditions and could therefore possibly benefit from the results of the quad test.
What if my quad screen results show my baby is at risk?
Because quad screen results are only indicators of risk, further tests are usually warranted to help determine what, if any, issues your baby is facing. Based on the severity of your test results your doctor might recommend other types of testing for further evaluation.
- Non-invasive ultrasounds
- CVS testing – Chorionic villus sampling
- Other extensive DNA testing
Keep in mind that there are mitigating factors that can influence the results of you quad screen, including a multiple pregnancy, the effects of in vitro fertilization, an incorrect calculation of your due date, health conditions like diabetes, and chemical interference from things like drugs and smoking. Genetic counselors are available to help you decipher the results of your quad testing so that you can make informed decisions regarding the health of your baby.