Two organizations issued a joint opinion on Nov. 20 that recommends that cell-free fetal DNA testing be offered to patients at increased risk of aneuploidy, an abnormal number of chromosomes. San Diego-based Sequenom Inc. (Nasdaq: SQNM), provides that screening in its MaterniT21 PLUS test, which analyzes the relative amount of 21, 18, 13 and Y chromosomal material in cell-free DNA.
The American College of Obstetricians and Gynecologists (ACOG) Committee on Genetics and the Society for Maternal-Fetal Medicine (SMFM) Publications Committee also said the DNA testing can be used as a follow-up test for women with a positive first-trimester or second-trimester screening test result.
Previously, the ACOG recommended that women, regardless of maternal age, be offered prenatal assessment for aneuploidy by screening or invasive prenatal diagnosis. The ACOG Committee on Genetics and the SMFM Publications Committee now recommend that women at increased risk of aneuploidy be offered cell-free fetal DNA as an option that can be used as a primary screening test based on the following indications:
• maternal age 35 years or older at delivery;
• fetal sonographic findings indicating an increased risk of aneuploidy;
• history of a prior pregnancy with a trisomy;
• positive test result for aneuploidy, including first trimester, sequential, or integrated screen, or a quadruple screen; and,
• parental balanced robertsonian translocation with increased risk for fetal trisomy 13 or 21.
The Committee Opinion also recommended that "cell-free fetal DNA testing should not be offered to low-risk women or women with multiple gestations because it has not been sufficiently evaluated in these groups." Further, the Committee Opinion stated that "pre-test counseling should be an informed patient choice after pre-test counseling and should not be part of routine prenatal laboratory assessment. A patient with a positive test result should be referred for genetic counseling and offered invasive prenatal diagnosis for confirmation of test results."
"The issuance of the ACOG/SMFM opinion on the use of cell-free fetal DNA testing represents a major step forward for the integration of this valuable technology into pregnancy care programs," said Allan Bombard, M.D., Sequenom's chief medical officer. "We fully support the indications for considering the use of cell-free fetal DNA outlined in the Committee Opinion and believe this will be a valuable tool to help guide physicians and their patients in the most appropriate prenatal care."