Non-invasive prenatal testing.

BACKGROUND Non-invasive prenatal testing (NIPT), also known as cell-free DNA testing and non-invasive prenatal screening (NIPS), is an important addition to the range of screening tests for fetal chromosomal abnormalities. For trisomy 21 in particular, NIPT is superior to other screening modalities. However, NIPT has limitations and complexities that requesting clinicians and their patients should understand. OBJECTIVE This review article will briefly describe the technical basis of NIPT assays and compare the performance characteristics of NIPT with existing screening tests. The clinical use of NIPT will also be discussed. DISCUSSION NIPT is now an established option for antenatal screening for trisomy 21, 18, 13 and other selected chromosomal abnormalities. If used appropriately, it increases the detection rate for fetal chromosomal abnormalities, while decreasing the number of invasive tests required. An understanding of the scientific basis of NIPT, and the appropriate clinical use and limitations, will enable medical practitioners to provide optimal antenatal screening.