Current Status in Non-Invasive Prenatal Detection of Down Syndrome, Trisomy 18, and Trisomy 13 Using Cell-Free DNA in Maternal Plasma

Abstract Objective To provide a review of published studies on the use of cell-free fetal DNA in maternal plasma for the non-invasive diagnosis of Down syndrome, trisomy 18, and trisomy 13. Evidence: PubMed was searched for articles published between 2006 and October 2012, using appropriate key words (e.g., non-invasive prenatal diagnosis, Down syndrome, cell-free fetal DNA, aneuploidy screening). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. Searches were updated on a regular basis and incorporated in the guideline to October 31, 2012. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. Values: The studies reviewed were classified according to criteria described by the Canadian Task Force on Preventive Health Care, and the recommendations for practice were ranked according to this classification (Table 1).