Review: advances in non-invasive prenatal diagnosis.

The invasive procedures amniocentesis and chorionic villus sampling are routinely applied in pregnancies at risk for fetal genetic disorders and the results obtained are the gold standard for prenatal diagnosis. These procedures have an approximately 0.5-1% risk for fetal loss and are mainly used in cases at risk for fetal chromosomal abnormalities and single-gene disorders. Identification of cell-free fetal nucleic acids (DNA and RNA) in maternal plasma and the recognition that they represent a useful source of fetal genetic material for prenatal diagnosis has led to intensive efforts to develop non-invasive prenatal testing. This review summarizes recent developments in the field of non-invasive prenatal diagnosis through the use of cell-free fetal nucleic acids in maternal circulation during pregnancy and provides an overview of the possibilities for future clinical applications.