On my first prenatal visit with my nurse midwife, they gave me a folder of useful information. One sheet laid out the purpose of each of my prenatal visits and their frequency, while a second sheet listed all of the prenatal testing options that we had. Since I would be over 35 when I gave birth, I had a few more testing options than younger mothers. Our prenatal provider didn’t discuss any of our test options at length, so I had to research most of them them on my own. Non-Invasive Prenatal Testing (or NIPT) is a newer test for a few select genetic anomalies which requires a blood sample. Here are a few things you should know about Non-Invasive Prenatal Testing before you consider having the test done.
Check for Non-Invasive Prenatal Testing Insurance coverage:
The first thing you should do is check with your insurance company for coverage, co-pay and/or deductible before you proceed with Non-Invasive Prenatal Testing. NIPT is very expensive if it isn’t covered and many plans apply the cost of your deductible. A few NIPT companies offer a rough estimate but I’ve heard that they can be very inaccurate. You should contact the company which your prenatal provider uses for NIPT and ask them for the billing code that they submit to your insurance company. You can find out directly from them if they cover Non-Invasive Prenatal Testing and how much you might have to pay out of pocket. I’ve read that some very surprised expectant moms received bills upwards of $800 because they didn’t meet criteria for coverage or all of the test cost was applied toward a deductible. If your plan doesn’t cover Non-Invasive Prenatal Testing, don’t stress; there are other tests available and women delivered babies without these tests for centuries.
How does Non-Invasive Prenatal Testing work?:
Non-Invasive Prenatal Testing is a blood test performed in your prenatal providers office or in a laboratory. The blood samples are shipped to a laboratory that performs Non-Invasive Prenatal Testing. There are several laboratory companies which offer NIPT, but almost all test for the exact same genetic anomalies in the fetus. They also all offer similar accuracy rates.
Try to understand the limitations of Non-Invasive Prenatal Testing:
Non-Invasive Prenatal Tests are not 100% accurate. They can provide (albeit low rates of) false positive and false negative results. One major misconception that people have is that the test examines fetal DNA, but all of the tests analyze placental DNA. In most cases fetal DNA is identical to placental DNA, but in rare cases something called placental mosaicism occurs. In cases of placental mosaicism fetal DNA will differ from placental DNA (I’m not getting into how or why) and this can cause inaccurate Non-Invasive Prenatal Testing results. Non-Invasive Prenatal Testing is only a diagnostic tool and follow-up testing should be conducted before any definitive diagnosis is made.
What does Non-Invasive Prenatal Testing screen for?:
- Down syndrome which is Trisomy 21
- Edwards syndrome which is also called Trisomy 18
- Patau syndrome which is also called Trisomy 13
- Turner syndrome which is also called Monosomy X
- Klinefelter syndrome which is also called XXY
- Triple X and XYY chromosomal syndromes
Does it matter when you have Non-Invasive Prenatal Testing done?
Many of the testing companies have a window in which they recommend testing; most of them say any time after 9 weeks. The number of women who receive results from testing at 9 weeks are small. There has to be enough free-cell DNA in maternal blood to receive a results, these numbers are referred to as fetal fraction. In most cases if the fetal fraction is below 4%, the company will ask for a redraw at a later date. I had first test at just over 10 weeks and the fetal fraction was too low for a result. I had a redraw roughly 2 weeks later and that sample had enough free-cell DNA to be deemed accurate. There are many things that can impact fetal fraction, but primarily fetal age, maternal height, and maternal weight play significant roles.
Be prepared to wait for Non-Invasive Prenatal Testing results:
Many companies state that results are ready between 5-6 business days following blood sample submission, but they doesn’t include transport time, computer entry, or a host of other delays. While researching this post, I found that most women receive results within 2 weeks. Our prenatal provider called us with the results roughly two days before they were available online.
Non-Invasive Prenatal Testing doesn’t produce positive or negative test results:
It would be easier to show you my results and then example them. My provider offers Panorama from Natera.
My results determined that my baby was at a low risk for the specified genetic anomalies. They calculate the risk prior to testing using age and other factors. The Panorama Risk Score was calculated using the free cell DNA. The fetal fraction for this test was 8.1%. Results are either assessed as low risk or high risk, so there are no positive or negative results. Any diagnosis would need to be made using additional testing methods.
This post was not intended to offer medical advice. I’m sharing my personal experience with Non-Invasive Prenatal Testing and research, so that expecting parents discuss NIPT with their own prenatal provider. I hope that you found this post helpful and I was able to explain the test in simple terms. Best wishes for a healthy and happy pregnancy.