Changing indications for invasive testing in an era of improved screening

Abstract

Prenatal diagnostic testing is available for a growing number of disorders. The goal of prenatal diagnosis was initially focused on the identification of Down syndrome in women aged 35 years and older, but invasive prenatal genetic techniques can now detect a far broader array of conditions. The risks of invasive procedures have also decreased over time. Advances in genomic medicine allow testing for smaller but significant chromosomal abnormalities known as copy number variants, in addition to major aneuploidies and structural rearrangements. Molecular DNA techniques can detect many single-gene conditions. In the future, it is likely that whole-exome and whole-genome sequencing will be applied to prenatal genetic testing to allow identification of yet more genetic disorders. With advances in technology, the indications for testing have likewise evolved far beyond recommendations based solely on maternal age to include a more patient-centered view of the goals of prenatal testing.

Keywords: Prenatal diagnosis; amniocentesis; chorionic villus sampling; chromosomal microarray; genetic counseling; karyotype.