Non-invasive prenatal detection of fetal aneuploidies by cell-free DNA, also called non-invasive prenatal testing (NIPT) and non-invasive prenatal screening (NIPS), is a method of non-invasive fetal DNA testing done through a maternal blood sample. NIPT testing for common aneuploidies, microdeletions and sex chromosome disorders is clinically available to patients in Canada. NIPT is a highly sensitive and specific screening test, but is not diagnostic. Even in high-risk populations, there can be false positive NIPT results. Genetic counselling, along with confirmatory testing via amniocentesis or chorionic villus sampling, should be done prior to using the result to impact management of a pregnancy.
Sources:
Benn P, et al. Ethical and practical challenges in providing noninvasive prenatal testing for chromosome abnormalities: an update. Curr Opin Obstet Gynecol. 2016 Apr;28(2):119-24. PMID: 26938150.
Mersy E, et al. Noninvasive detection of fetal trisomy 21: systematic review and report of quality and outcomes of diagnostic accuracy studies performed between 1997 and 2012. Hum Reprod Update. 2013 Jul-Aug;19(4):318-29. PMID: 23396607.