Prenatal Genetic Screening: Is it Necessary?

You may have heard people talk about genetic testing and screening once you become pregnant. Don’t worry – we’re here to help you understand what this means. Learn more about these tests below and whether they are appropriate for you.

Genetic testing is a way of evaluating if the baby may have a genetic disorder before birth. The procedure of screening and testing helps to identify pregnancies as high risk for Down syndrome and other chromosomal disorders. The tests will signal if a chromosome is missing or an extra one is present (referred to as aneuploidy), leading to a disorder that, in some cases, may require special treatment and be life-limiting or life-threatening. 

• Screening tests will tell you the chance that your baby might have a disorder.
  • Prenatal Screening Tests:
    • The screening uses a pregnant woman’s blood and often an ultrasound to look for aneuploidy (extra or missing chromosome) in the fetus or defects in the brain and spine of the fetus (neural tube defects.)
    • Several different types of tests are required to complete the screening. Choosing the proper test for you will depend on your age, history, gestational age, and insurance coverage. We will guide and support you in making the best choice for your pregnancy.
    • Depending on the screening test chosen for you, most people can also find out the gender of their baby with this test. 

• Diagnostic testing, often done after a positive result on the screening test (above), will tell you definitively whether or not your baby has a genetic disorder by testing cells from the amniotic fluid or placenta. 
  • Amniocentesis: In this diagnostic test, a needle is used to collect a sample of amniotic fluid from the uterine cavity via the mother’s abdomen.
  • Chorionic Villus Sampling (CVS): In this test, a needle and/or catheter is used to collect a placenta sample via the abdomen or the cervix.

Completing these screening and diagnostic tests is a personal decision that should reflect your beliefs and values. This decision is the first of many tough choices you’ll make as a new parent, and there is no right or wrong choice. Some people want to know as much as possible before delivery, and if the screening returns positive, they choose to move on to diagnostic testing. Often, these women want to be as prepared as possible for the baby’s arrival. Still, others may choose not to have any testing and to take it as it comes, if it comes. 

We are happy to review the options for testing and screening with you to help guide you to the right decision—the one that works best for you and your family.