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Is Prenatal Testing for Disease and Birth Defects a Good Idea?

There is a debate among would-be parents and experts alike, as to whether it’s better to undergo prenatal genetic testing and know if there is a problem – or not. Here are the pros and cons.
A pregnant woman undergoes an ultrasound.
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Expecting a baby can be one of the most joyous times in a couple’s life together. It can also instill a lot of worry. One of the biggest concerns is over the baby’s health. They may worry about birth defects or even genetic diseases. Luckily, most babies are born perfectly healthy. That doesn’t mean such complications are rare, but uncommon. Around one in 33 births result in a birth defect each year, according to the CDC.


Prenatal testing is by and large up to the woman or the couple. There are generally two types: screening and diagnostic tests. First trimester screening usually occurs around 10 to 13 weeks. This includes a blood test and an ultrasound, which can detect whether or not the baby might develop Down syndrome.

During the second trimester a quad screen can be performed. This can test for certain chromosomal indicators which may signal the presence of Down syndrome, along with neural tube defects, or issues with the brain or spinal cord. Keep in mind that even if such testing does come back positive, it doesn’t necessarily mean the child is doomed to a certain condition.

A diagnostic test is usually delivered if there is some sort of family history of a disease, if the mother is of a certain age, if a parent’s medical history puts the baby at risk, or another test unearths a potential problem. This is the only way to know what’s going on for sure. Usually, these are invasive, which is one of the reasons why it has to be considered carefully. In these instances, a sample of the amniotic fluid—known as amniocentesis, or of the placenta—called chorionic villus sampling (CVS), can be performed.

Advancements in medicine have given prospective parents a lot of complex decisions to make, such as what type of prenatal testing should be employed.

Lastly, there is a newcomer to the group: cell-free DNA screening. This is a blood test which examines the DNA of the fetus found in the mother’s bloodstream. It can check for specific chromosomal issues, such as Down syndrome, Tay-Sachs disease, cystic fibrosis, or sickle cell anemia. Though birth defects may occur at any point in the pregnancy, according to the CDC, they are most likely to occur in the first trimester. Currently, there is a debate among would-be parents and experts alike, as to whether it’s better to undergo prenatal genetic testing and know if there is a problem or not. Here are the pros and cons.

PRO:

  • A negative test can allay parents’ fears and ease tension.
  • A positive one can help prepare the parents and let them know what to expect.
  • Parents can start saving for the care their child if disability is detected.
  • Testing can allow them to decide whether or not to keep the pregnancy.
  • CON:

    • A positive result can cause the parents anxiety and inner conflict.
    • The stress of knowing can affect their relationship.
    • Those with disabilities today can lead useful, fulfilling, vibrant lives.
    • Genetic screening can give a false positive, causing anxiety for no reason.
    • There may be a chromosomal issue the test misses.
    • Prenatal testing is optional. Some physicians suggest thinking about why a potential parent wants to know before deciding. This could help develop an understanding of whether or not it’s right for them. Dr. Andrea Greiner is a maternal and fetal medicine specialist at the University of Iowa Hospitals and Clinics. She told Live Science that most women don’t undergo such testing to know whether or not to have an abortion, but merely to prepare themselves.

      Some women should evaluate whether or not a positive answer would lead to undue stress, the specialist said. Dr. Greiner also notes that this science is new, and patients should keep that in mind. If you are considering prenatal testing, be sure to ask your doctor a lot of questions before deciding.

      To learn how aging affects pregnancy and prenatal testing, click here: 

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