Spotlight on Prenatal Genetic Testing

According to a recent NPR article, the amount of prenatal genetic testing available to expectant parents has increased enormously over the last decade (1). Furthermore, the genetic testing industry is expected to continue growing by nearly 30% over the five years ahead (1).

What are genetic tests used for?

Prenatal genetic testing is used to provide insights into the likelihood that a fetus may have a number of different genetic disorders (2,3). According to the Center for Disease Control and Prevention (CDC), roughly 3% of babies are born with genetic disorders (4). Such genetic disorders include:

  • Trisomy: An extra chromosome. Down Syndrome is known as Trisomy 21.
  • Monosomy: A missing chromosome.
  • Aneuploidy: Missing or extra chromosomes.
  • Sickle cell disease
  • Tay-Sachs disease
  • Cystic fibrosis

What types of genetic tests are given?

There are two types of prenatal genetic tests (2,3):

  • Screening tests: Tests that reveal the chances a fetus may have a disorder. There are two major types of screening tests:
    • Carrier screenings (a blood sample or a tissue sample is taken from the inside of the parents’ cheeks)
    • Prenatal genetic screenings (a test of the blood and ultrasound findings). Such screenings include the quad screen, nuchal translucency (NT), and noninvasive prenatal testing (NIPT).
  • Diagnostic tests: Tests that tell with as much certainty as possible whether a fetus has a genetic disorder. Such diagnostic tests are chorionic villus sampling and amniocentesis, and they are all invasive tests (meaning they come with associated risks).

How much do genetic tests cost?

Prenatal genetic tests may be covered by your insurance. Many screenings are covered by insurance, and diagnostic tests may be covered if you are high-risk, over 35, or if you received abnormal results on a screening test (5). Fox News estimates the costs of prenatal genetic testing to be anywhere between $800 – $2,000 per test (6). Insurances are covering more of these tests now than they did in the past, so talk to your insurance provider about which tests they will cover.  

Should I get genetic testing done?

With so many tests available, the question of whether someone should get a test done is a big one. Knowing your baby’s risk of genetic disorders can help parents prepare for their care and medical needs throughout life.

NPR notes that, for many families, however, knowing the results of genetic screenings and diagnostic tests can create more anxiety during pregnancy (1). It is also important to note that many of these tests are for very rare disorders and diseases that aren’t well-understood at this moment, so, even if the child had the disorder, knowing the prognosis is hard to do with certainty.

The decision to have prenatal testing offered by your doctor is entirely yours and should be made with your beliefs, values, and informed considerations at the forefront. ACOG emphasizes that screening tests only show the possibility of having a child with certain disorders (2). A diagnostic test is required if you want to know with more certainty. Many parents decide not to have any testing at all, and there is no right choice when it comes to genetic testing.

Genetic counseling

If you’re unsure about genetic testing, you may want to meet with a genetic counselor. Genetic counselors are professionals who interpret genetic tests and advise potential or expectant parents about their child’s risk of having genetic disorders. Anyone can see a genetic counselor, but it is especially encouraged if the patient (4):

  • or their partner has a family history of chromosomal abnormalities or genetic disorders
  • has had recurrent miscarriages
  • has had a stillbirth or an infant death
  • is a known carrier of a genetic or a chromosomal disorder
  • and their partner are related or from the same family line
  • has been exposed to an infection, illness, or toxin that could affect the baby
  • is of advanced maternal age (over 35)
  • or their partner has received abnormal results on genetic screening tests

Sources

  1. McClurg, L. (2019, April 08). Prenatal Testing Can Ease Minds Or Heighten Anxieties. Retrieved April 27, 2019, from https://www.npr.org/sections/health-shots/2019/04/08/710204097/prenatal-testing-can-ease-minds-or-heighten-anxieties
  2. Women’s Health Care Physicians. (2017, July). Retrieved April 27, 2019, from https://www.acog.org/Patients/FAQs/Prenatal-Genetic-Screening-Tests?IsMobileSet=false
  3. Women’s Health Care Physicians. (n.d.). Retrieved April 27, 2019, from https://www.acog.org/Patients/FAQs/Prenatal-Genetic-Diagnostic-Tests?IsMobileSet=false
  4. Murray, D., Fogoros, R. N., & Bsn. (2019, March 11). Risks, Causes, and Information on Genetic Disorders in Pregnancy. Retrieved April 29, 2019, from https://www.verywellfamily.com/pregnancy-and-genetic-disorders-4172801
  5. Editors, W. T. (2017, May 17). The 6 Most Common Genetic Screenings and Tests During Pregnancy. Retrieved April 29, 2019, from https://www.whattoexpect.com/pregnancy/pregnancy-health/prenatal-testing-most-common-genetic-tests-during-pregnancy/
  6. Revelant, J. (2015, October 24). New prenatal genetic tests: Are they for you? Retrieved May 2, 2019, from https://www.foxnews.com/health/new-prenatal-genetic-tests-are-they-for-you

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