Prenatal testing has made it possible for health care providers, to determine whether certain individuals are at risk for problems during pregnancy. Many expectant parents may worry over the health of their baby, even during the early stages of pregnancy. With the advent of prenatal testing, it has made pregnancies a more guarded experience for many women. Although not all conditions affecting an unborn child can be detected, these tests can help in terms of anticipating any special care that a baby may need even before birth.
Among the common prenatal tests is the quad marker screen or the maternal serum marker. This test is optional, but it is normally ordered during the 15-20th week of pregnancy. It is primarily ordered for women who are 35 years old or older, or for women who have a family history of birth defects. It is also ordered for women having Type 1 diabetes prior to the pregnancy. The doctor may also order this test for women who have been exposed to high levels of radiation, or for women who may have used harmful drugs during pregnancy.
The test does not put a woman and her unborn baby at risk for any complications. It simply involves the drawing of blood, so that the sample can be sent to the laboratory for analysis. This test is ordered to measure the level of four specific substances in the maternal blood. Here are the four specific substances being tested and their possible implications:
1. AFP or alpha-fetoprotein – AFP is a protein produced by the fetus. An elevation of this protein may indicate that a baby may have a neural tube defect like spina bifida or anencephaly. However it may also indicate inaccurate dating of the pregnancy. An elevated AFP may also indicate that a woman may be expecting twins. Low AFP levels on the other hand, may indicate that a woman has a higher risk for carrying a baby with Down syndrome.
2. hCG – This hormone is produced by the placenta. High levels of hCG may indicate that a woman has an increased risk of having a baby with Down syndrome.
3. Estriol – This hormone is produced by the placenta and the baby’s liver during pregnancy. Elevated levels may indicate a higher risk of a woman to carry a baby with Down’s syndrome.
4. Inhibin A – This hormone is produced during pregnancy, and elevated levels may indicate that a woman has a higher risk of having a baby with Down syndrome.
It is very important to note that the levels of these substances in the maternal blood, changes as pregnancy progresses. Thus, it is important for the tests to be done on the specific time period it is intended for. And although some women may get abnormal results, it does not directly indicate that there is indeed a problem with the pregnancy. The doctor still needs to do further testing to determine whether any abnormalities are really present.
If you are thinking whether it is worth all the anxiety, it may be best to discuss with your doctor whether you really need to undergo such testing. But the results are significant because it can indicate, whether you have an increased risk of having a baby, with developmental or chromosomal problems. It can predict approximately 75% cases of Down syndrome for women under 35 years old, and over 80% of Down syndrome cases for women 35 years and older. To add to that, it can predict up to 75-80% of cases of open neural tube defects in babies.
The decision of couples to undergo this test may greatly depend on the circumstances surrounding the pregnancy. Thus, it is best to talk to your doctor whether or not this test may be beneficial for you and your baby.