Your health care provider or a genetic counselor will explain the results of noninvasive prenatal testing. For example:
- Chromosomal conditions. If the test results are normal, you might not need further testing. However, if results indicate the likelihood that your baby has a chromosomal abnormality, amniocentesis or CVS will be offered. Further testing using the sample from amniocentesis or CVS can be used to confirm the diagnosis.
- Fetal sex. If you're the carrier of an X-linked recessive disorder and the test results indicate that you're carrying a girl, you might not need further testing. If the test results indicate that you're carrying a boy, amniocentesis or CVS will be offered. These tests can be used to diagnose a genetic condition.
- Rh factor. If you're Rh negative and the test results indicate that your baby is Rh negative, you won't need medication to prevent your body from producing Rh antibodies during your pregnancy. If the test results indicate that your baby is Rh positive and you've previously become sensitized, your baby will be carefully monitored.
Chromosomal abnormalities can't be corrected. If your baby is diagnosed with a chromosomal abnormality, you'll need to decide whether to continue with your pregnancy or what steps to take to care for your baby during pregnancy and after he or she is born. Your health care provider or a genetic counselor can help answer any questions you might have.
Keep in mind that regardless of the results of noninvasive prenatal testing, if you have risk factors that suggest your baby might be at increased risk of a chromosomal condition you have the option of undergoing amniocentesis or CVS.
Feb. 23, 2013
- National Society of Genetic Counselors Public Policy Committee, et al. Noninvasive prenatal testing/noninvasive prenatal diagnosis: The position of the National Society of Genetic Counselors. National Society of Genetic Counselors. http://www.nsgc.org/Advocacy/PositionStatements/tabid/107/Default.aspx. Accessed Dec. 7, 2012.
- Allyse M, et al. Cell-free fetal DNA testing for fetal aneuploidy and beyond: Clinical integration challenges in the US context. Human Reproduction. 2012;27:3123.
- Wright CF, et al. Non-invasive prenatal diagnostic test accuracy for fetal sex using cell-free DNA a review and meta-analysis. BMC Research Notes. 2012;5:476.
- Devaney SA, et al. Noninvasive fetal sex determination using cell-free fetal DNA: A systematic review and meta-analysis. Journal of the American Medical Association. 2011;306:627.
- Chiu RWK, et al. Non-invasive prenatal assessment of trisomy 21 by multiplexed maternal plasma DNA sequencing: Large scale validity study. British Medical Journal. 2011;342:c7401.
- Shulman LP. One small step and one giant leap for noninvasive prenatal screening: An editorial. American Journal of Obstetrics and Gynecology. 2011;204:183.
- Ehrich M, et al. Noninvasive detection of trisomy 21 by sequencing of DNA in maternal blood: A study in a clinical setting. American Journal of Obstetrics and Gynecology. 2011;204:205e1.
- Palomaki GE, et al. DNA sequencing of maternal plasma to detect Down syndrome: An international clinical validation study. Genetics in Medicine. 2011;13:913.
- Frequently asked questions. Pregnancy FAQ133. Routine tests in pregnancy. American College of Obstetrics and Gynecology. http://www.acog.org/~/media/For%20Patients/faq133.pdf?dmc=1&ts=20121207T1430460501. Accessed Dec. 7, 2012.
- Down syndrome overview. National Institute of Child Health & Human Development. http://www.nichd.nih.gov/health/topics/down/Pages/default.aspx. Accessed Dec. 7, 2012.
- Sehnert AJ, et al. Optimal detection of fetal chromosomal abnormalities by massively parallel DNA sequencing of cell-free fetal DNA from maternal blood. Clinical Chemistry. 2011;57:1042.
- What is Down syndrome? National Down Syndrome Society. http://www.ndss.org/Down-Syndrome/What-Is-Down-Syndrome/. Accessed Dec. 7, 2012.
- Diagnostic tests for birth defects. American College of Obstetrics and Gynecology. http://www.acog.org/Resources_And_Publications/Patient_Education_Pamphlets/Files/Diagnostic_Tests_for_Birth_Defects. Accessed Dec. 7, 2012.
- Rijinders RJP, et al. Clinical applications of cell-free fetal DNA from maternal plasma. Obstetrics and Gynecology. 2004;103:157.
- Wick Myra J (expert opinion). Mayo Clinic, Rochester, Minn. Dec. 22, 2012.
- The American College of Obstetricians and Gynecologists Committee on Genetics and the Society for Maternal-Fetal Medicine Publications Committee. Committee Opinion No. 545: Title of committee opinion. Obstetrics & Gynecology. 2012;120:1532.