cfDNA Results

Interpreting any prenatal genetic screening result can be challenging. Because of this, it may be helpful to meet with a specialist, such as a genetic counselor, who can review the specifics of your situation to help you understand what your cfDNA results mean for your pregnancy.

It is important to remember that cfDNA results, just like other screening results, do not give a ‘yes’ or ‘no’ answer to whether a pregnancy has a chromosome condition. cfDNA may tell you whether the pregnancy is at increased or decreased risk for the conditions that are being tested.

For tests that can provide you with a definitive ‘yes’ or ‘no’ answer, read more about prenatal diagnostic testing.

There are many labs that perform cfDNA testing, and each lab may report their results out in a slightly different way. Here are some examples:

  • Positive (increased risk) or negative (decreased risk)
  • Aneuploidy detected (increased risk) or no aneuploidy detected (decreased risk)
    • Aneuploidy = extra or missing chromosome material was found
  • High risk, intermediate risk, or low risk

Most labs will give you a separate result for each of the conditions they are screening for. For example, you may get a positive/high risk result for Down syndrome, but negative/low risk results for trisomy 18, trisomy 13, etc.

There are some additional things to keep in mind with regard to cfDNA screening results:

  • How well the test works for Down syndrome, trisomy 18, trisomy 13, and other chromosome conditions varies widely. It is important to discuss your results with your provider to understand what they mean for you and your pregnancy.
  • Not all labs screen for the same conditions.
  • cfDNA screening can often tell if the baby is a boy or a girl. However, there is a small possibility that the test will predict fetal sex incorrectly.
  • cfDNA screening does not test for all chromosome differences or birth defects.
  • In some cases, cfDNA screening can find evidence of other health conditions that are present either in the baby or in the mother that were not expected.
    • For example, cfDNA screening in rare cases has identified that a pregnant mom has cancer.

This is a basic overview of cfDNA screening results. It is important to meet with a specialist, such as your doctor or a genetic counselor, to understand what these results mean for you and your pregnancy.

Click here to learn more about scheduling a genetic counseling appointment for pregnancy-related questions.

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Last updated on Aug 21st, 2019

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