Pregnancy Comes With Questions

Pregnancy is an exciting time that comes with a lot of questions. One of them is, “Will my baby be healthy?” Fortunately, noninvasive prenatal testing, or NIPT, exists and can help you get some answers about genetic health. NIPT consists of a simple blood test done as early as 10 weeks of pregnancy. It can screen for certain chromosomal conditions such as:

• Down syndrome (trisomy 21)
• Edwards syndrome (trisomy 18)
• Patau syndrome (trisomy 13)
• Sex chromosome conditions
• In addition, there are options to also screen for other more rare chromosomal abnormalities.

The Answers You Are Looking For
As a screening test, NIPT will tell if your baby is likely to have one of these conditions, but it will not give you a definite answer. A diagnostic test such as amniocentesis or chorionic villus sampling (CVS) will provide a “yes” or “no” answer, but both come with a small risk for miscarriage or pregnancy complications. Professional societies like the American College of Obstetricians and Gynecologists (ACOG) recommend that all women be offered screening or testing for chromosomal conditions during pregnancy.¹

You can consider NIPT if:

• You are currently 10 weeks pregnant or more.
• You want reassurance about your baby’s genetic health.
• In addition, your doctor may suggest NIPT if you have a higher risk for a genetic abnormality in this pregnancy.

Most women will receive normal NIPT results that are reassuring. In the case of a positive result, your doctor will discuss further testing options to consider. You should not make any permanent decisions about your pregnancy based on a screening test such as NIPT alone. As with all screening tests, there is a chance that the results may not be correct.

Answers You Can Trust
Screening for certain chromosomal conditions during pregnancy has been around for a long time. Your doctor’s office may still offer other options, like first trimester or sequential screening. NIPT screens for more chromosomal conditions than the other screening options, and it has proven to provide the most accurate prenatal screening.¹ NIPT offers both the highest detection rate and the lowest false positive rate, which is the lowest chance that the test will come back with a positive result when your baby does not have a chromosomal condition. NIPT is also available beginning at 10 weeks of pregnancy, while other screening tests may only be available for a small window of time during pregnancy. If you pursue NIPT, your doctor may still recommend another blood draw or an ultrasound to screen for open neural tube defects, like spina bifida, which NIPT does not screen for.

What You Can Do Next
If you are interested in pursuing NIPT during your pregnancy, talk to your doctor. Your decision to screen for chromosomal conditions during pregnancy is your choice. Many different NIPT tests are available, so you should talk to your doctor about how the tests are performed, what conditions they screen for, how their results are reported, and what the chances are that they will not provide a result (i.e., a “test failure”), so you can choose the right NIPT for you. Talk to your doctor or a genetic counselor about what a positive test result could mean for you and your baby.

For more information about NIPT, visit www.illumina.com/NIPTExpecting

NIPT is a maternal blood screening test and evaluates DNA from your pregnancy that is circulating in your blood. Screening tests are not diagnostic or definitive. Because there is a small possibility that a screening result might be incorrect, it is important to talk to your doctor to determine if further testing is needed. 

Reference
¹American College of Obstetricians and Gynecologists. Practice bulletin no. 163: Screening for fetal aneuploidy. Obstet Gynecol. 2016;127(5):e123-137.

— By Patty Taneja, MS, LCGC
Senior Genetic Counselor