To provide women with accurate information regarding genetic screening and diagnostic testing in pregnancy, two revised practice bulletins have been released by the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM).
The two practice bulletins, Screening for Fetal Aneuploidy and Prenatal Diagnostic Testing for Genetic Disorders, clarify the purposes of and differences between prenatal genetic screening and prenatal diagnostic testing to aid clinicians in providing their patients with the most up-to-date, accurate information.
“Although it is important to offer all women screening or diagnostic testing for genetic disorders, there is no one test that is superior to others,” said Nancy C. Rose, MD, former chair of the ACOG Committee on Genetics and lead author of Screening for Fetal Aneuploidy. She added, “Furthermore, testing should be an informed patient choice.… Women have the right to decline both genetic screening and testing, and all decisions should be supported.”
Prenatal genetic screening assesses whether a patient is at an elevated risk of having a fetus affected with a genetic disorder; prenatal diagnostic testing is used to diagnose whether a specific genetic disorder is present in the fetus. All women with positive screening results should be offered additional diagnostic testing and counseling.
Screening for Fetal Aneuploidy makes note of an additional screening option known as Cell-free DNA (cfDNA) screening. This test is a “rapidly evolving area of pregnancy care,” but like all genetic testing and screening, is susceptible to both false positives and false negatives. All tests, including cfDNA, require confirmation via amniocentesis or chorionic villus sampling.
“It is important to note that diagnostic testing is safe and should be available to all women,” concluded Mary E. Norton, MD, president of the SMFM and lead author of Prenatal Testing for Genetic Disorders.
- Ob-Gyns release revised recommendations on screening and testing for genetic disorders [news release]. Washington, D.C.: American Congress of Obstetricians and Gynecologists. Published March 1, 2016. Accessed March 11, 2016.