Pregnancy is an exciting time, but also a little nerve-racking because of all the unknowns that come along with having a baby. One of the primary concerns families have is the health of their newborn. Although no prenatal tests can “guarantee” a perfectly healthy baby, it is comforting to know there are prenatal testing options to help determine if there may be health issues with the baby.
Some of the more common conditions affecting pregnancies involve chromosomal abnormalities - with the most common being Down syndrome.2 Fortunately, over the years, tests have been designed to help us look for these conditions.One of the newer tests is something called Non-Invasive Prenatal Testing (NIPT). NIPT is a screening test for pregnant women to help figure out their chances for having a baby with Down syndrome (Trisomy 21), Edwards syndrome (Trisomy 18) or Patau syndrome (Trisomy 13). The test also is often able to indicate whether the baby is a boy or girl.
The way NIPT works is really cool.3 What we’ve learned is that very small pieces of DNA from the pregnancy go into mom’s blood. We now have the technology to find these little pieces and to figure out which chromosome they come from. We then look at the amount of each chromosome in the blood. The hope is that there is a certain balance between the chromosomes.
To illustrate, since there are typically two copies of each chromosome, the amount of DNA from chromosome 21 should be the same as chromosome 18. But if there was MORE DNA from chromosome 21 than expected, then the question would be “why is there more”? The answer is that there is probably a THIRD copy of chromosome 21 in the pregnancy (so the pregnancy would release MORE DNA from chromosome 21 then the other chromosomes). If there is an extra copy of chromosome 21 in the pregnancy, then we would expect that baby to have Down syndrome.
NIPT is the most accurate screening test available for these conditions 3-7 and is performed by a simple blood test. The test is available any time after 10 weeks gestation and results usually take around one week. If the NIPT results indicate there is a high chance for the baby to have one of these conditions, then diagnostic testing options would be offered to the mother to provide a definitive yes or no answer. Studies have shown that NIPT can find more pregnancies with these conditions and is accurate more often than other screening tests, including First trimester screening, Quad screening, or Triple marker screen.3-7
PerkinElmer, ViaCord’s parent company, recently launched Vanadis® NIPT. Vanadis® NIPT was developed using innovative technology that allows NIPT to be performed in a simple, highly accurate and much more cost-effective way. Our hope is that PerkinElmer’s Vanadis® NIPT System will give more women access to better prenatal testing. If you are interested in any NIPT test, a discussion with your healthcare provider or a genetic counselor to fully understand the benefits, limitations and cost of this test is highly recommended.
About Our Guest Bloggers
Lawrence Prensky – Medical Education Manager, PerkinElmer
Lawrence is a certified genetic counselor who has co-authored multiple peer-reviewed publications and provided multiple presentations. Prior to joining PerkinElmer, Lawrence was a clinical genetic counselor for over 20 years, mainly helping pregnant couples. He claims to be not nearly as cool as Shelly and remains dismayed that even though he has counseled tens of thousands of patients, not one of them has named their baby after him.
Shelly Lopez-Gray – Sales Scientist, PerkinElmer
Shelly Lopez-Gray is a registered nurse behind the blog Adventures of a Labor Nurse: the Highs and Lows of Labor and Delivery. She works as a Sales Scientist for Vanadis® NIPT. Shelly volunteers teaching prenatal classes to women at a pregnancy crisis center and provides breastfeeding information to mothers at a teen clinic. Shelly is dedicated to the health of moms and babies and genuinely believes that every person has the potential for greatness.
Note: PerkinElmer and ViaCord do not endorse or make recommendations with respect to research, medications or treatment. All information is provided for informational purposes only. For country specific recommendations, please consult your healthcare professional. Pursuant to applicable federal and/or state laboratory requirements, PerkinElmer Genomics establishes and verifies the accuracy and precision of their testing services.
References
1 – Gardner, R. and Sutherland, G (2004). Chromosomes abnormalities and genetic counseling 3rd ed. P. 366. Oxford: Oxford University Press
2 – Dahl F, Ericsson O, Karlberg O, et al.; Imaging single DNA molecules for high precision NIPT. Scientific Reports 2018;8:4549
3- Practice Bulletin No. 163: Screening for fetal aneuploidy. Obstet Gynecol. 2016;127(5):979-81.
4 - Gregg AR, Skotko BG, Benkendorf JL et al. Noninvasive prenatal screening for fetal aneuploidy, 2016 update: a position statement of the American College of Medical Genetics and Genomics. Genet Med. 2016;18(10):1056-65.
5 - Bianchi DW, Parker RL, Wentworth J, et al.; CARE Study Group. DNA sequencing versus standard prenatal aneuploidy screening. N Engl J Med 2014;370:799–808.
6 - Norton ME, Jacobsson B, Swamy GK, et al. Cell-free DNA analysis for noninvasive examination of trisomy. N Engl J Med 2015;372:1589–1597.
7 - Zhang H, Gao Y, Jiang F, et al. Non-invasive prenatal testing for trisomies 21, 18 and 13: clinical experience from 146,958 pregnancies. Ultrasound Obstet Gynecol 2015;45:530–538.
