Noninvasive prenatal testing: limitations and unanswered questions

Monica A. Lutgendorf MD,

Katie A. Stoll MS,

Dana M. Knutzen MS

& Lisa M. Foglia MD

Affiliations

Corresponding author

Genetics in Medicine

(2013)

doi:10.1038/gim.2013.126

Received: 07 June 2013
Accepted: 10 July 2013
Published online: 05 September 2013

Abstract

The clinical use of noninvasive prenatal testing to screen high-risk patients for fetal aneuploidy is becoming increasingly common. Initial studies have demonstrated high sensitivity and specificity, and there is hope that these tests will result in a reduction of invasive diagnostic procedures as well as their associated risks. Guidelines on the use of this testing in clinical practice have been published; however, data on actual test performance in a clinical setting are lacking, and there are no guidelines on quality control and assurance. The different noninvasive prenatal tests employ complex methodologies, which may be challenging for health-care providers to understand and utilize in counseling patients, particularly as the field continues to evolve. How these new tests should be integrated into current screening programs and their effect on health-care costs remain uncertain.
Genet Med advance online publication 5 September 2013

Keywords:

aneuploidy; cell-free DNA; genetic counseling; noninvasive prenatal screening; noninvasive prenatal testing

Screening for Aneuploidy in Pregnancy

The past 2 decades have seen major advances in prenatal screening for chromosomal conditions, most recently in the realm of noninvasive prenatal testing (NIPT). These tests evaluate circulating cell-free DNA (cfDNA) to determine the risk of fetal aneuploidy. In pregnancy, cfDNA in maternal blood is a mixture of maternal DNA and placental DNA from apoptosis of placental cytotrophoblasts. The circulating cfDNA can be analyzed to identify qualitative and quantitative differences between the maternal and the placental DNA.