(HealthDay)—Cell free fetal DNA testing is an effective screening tool for fetal aneuploidy and should be offered to high-risk women, but should not form part of routine prenatal laboratory assessment, according to a Committee Opinion published in the December issue of Obstetrics & Gynecology.
The American College of Obstetricians and Gynecologists' Committee on Genetics and the Society for Maternal-Fetal Medicine Publications Committee reviewed emerging clinical and scientific data on the use of noninvasive prenatal testing using cell free fetal DNA from the plasma of pregnant women.
The authors recommend that cell free fetal DNA testing should only be offered to patients at increased risk of aneuploidy. Testing can identify about 98 percent of Down syndrome cases with a less than 0.5 percent false-positive rate. Testing has not been sufficiently evaluated in low-risk women or those with multiple gestations and consequently should not be offered to these groups. Pretest counseling should be used to inform patients of their choices and should emphasize that a negative test does not ensure an unaffected pregnancy. Testing can only screen for common trisomies and does not provide other genetic information about the pregnancy. Patients with a positive result should be referred for genetic counseling and offered invasive testing to confirm the results.
"Although no prospective trials of this technology are available, cell free fetal DNA appears to be the most effective screening test for aneuploidy in high-risk women," the authors write.
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