Cell-free DNA Testing – No-Call Results

With cfDNA testing, there is a possibility to get a no-call result. A no-call result means that the lab was not able to run the test, or that the test did not yield a result.

There are a few possible reasons that prenatal cfDNA screening may not provide a result. It could be due to poor DNA quality, or due to a problem with the shipping of the sample. Some labs look at something called fetal fraction. Fetal fraction represents the percentage of placental DNA that is floating around in mom’s blood.

Many women will get a result if they have the cfDNA screening repeated with a second blood draw. Some studies have indicated that receiving a no-call result may mean there is an increased risk for a chromosome condition, such as Down syndrome. Your doctor may offer you a diagnostic test, such as chorionic villus sampling (CVS) or amniocentesis to get more information. Diagnostic tests can provide more definitive information, but comes with a usually small risk for miscarriage.

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Last updated on Apr 7th, 2018