H prenatal genetic diagnosis for numeric chromosomal abnormalities (trisomy 21) at last reached its desired goal of becoming a definitive test (not a screen)? Can we relegate our invasive diagnostic procedures— chorionic villus sampling (CVS) and amniocentesis—to the museum? The contributions of Bianchi et al1 (see p. 890) and others earlier this year2,3 take us a considerable distance. Of cour...

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). Resu...

Cell-free DNA testing is a recently introduced method for screening pregnant women for fetal trisomy, which is associated with some common significant genetic diseases, as well as the sex of the fetus. The case described here demonstrates the connection between the ultrasound "vanishing twin" phenomenon and the misdiagnosis of prenatal sex using cell-free DNA testing.

BACKGROUND Cell-free fetal DNA (cff DNA) and RNA can be detected in maternal plasma and used for non-invasive prenatal diagnostics. Recent technical advances have led to a drastic change in the clinical applicability and potential uses of free fetal DNA and RNA. This review summarizes the latest clinical developments in non-invasive prenatal diagnosis in the context of the latest technical deve...