![]() ![]() Women who pursue first-trimester screening alone should be offered maternal serum AFP testing in the second trimester to screen for neural tube defects. Genetics counseling and chorionic villus sampling or amniocentesis should be offered to all women with elevated risk, as determined by serum screening. Women with isolated nuchal thickening or isolated maternal serum AFP (with normal ultrasonography and normal karyotype) should be followed closely because they are at increased risk of poor pregnancy outcomes.Ĭombined first- and second-trimester screening offers superior detection rates while maintaining low false-positive rates. Quadruple screening is recommended for second-trimester screening. Pregnant women should be offered screening and invasive diagnostic testing regardless of age.Ĭombined testing is recommended for first-trimester screening. Specific screening tests will depend on availability of the procedure and patient preference. Comprehensive counseling should be available to all pregnant women. For women who do not present until the second trimester, the quadruple screen is recommended. If nuchal translucency testing is unavailable, the maternal serum-integrated test is safest and most effective. An integrated test with nuchal translucency testing is the most effective method for women who present in the first trimester. These options include an analysis of pregnancy-associated plasma protein A, with or without nuchal translucency testing, in combination with quadruple screening. Patients may also choose a combination of first- and second-trimester screening in an integrated, stepwise sequential, or contingent sequential fashion. Screening options in the second trimester include serum screening using triple or quadruple screening, and ultrasonography. Nuchal translucency testing alone is not as effective. Screening options in the first trimester include nuchal translucency testing in combination with measurement of pregnancy-associated plasma protein A and human chorionic gonadotropin. Diagnostic options include chorionic villus sampling in the first trimester and amniocentesis in the second trimester. New developments in screening methods have increased the number of options for patients. It is also important to note that much of the information available regarding how reliable this test is comes from studies funded by the commercial labs and/or authored by individuals associated with one of the commercial labs.Ĭlick here to learn more about scheduling a genetic counseling appointment for pregnancy-related questions.Pregnant women of all ages should be offered screening and invasive diagnostic testing for chromosomal abnormalities before 20 weeks’ gestation. On the other end, a false negative result is when a test comes back negative for a condition but the pregnancy actually has the condition.Ĭurrently, cfDNA is not regulated by the FDA. A false positive result is when a test comes back high risk for a condition, such as trisomy 18, but the pregnancy does not actually have trisomy 18. It is important to discuss with your provider what your cfDNA test will screen for, and to come to a plan that is best for you and your family.īoth cfDNA and traditional screening tests have the possibility of a false positive or false negative result. Some labs offer screening for other genetic conditions, such as microdeletion syndromes, for which there is limited available data. cfDNA is also able to test for sex as well as sex chromosome differences (more or fewer X or Y chromosomes than expected). ![]() Traditional screening tests can also detect an increased risk for pregnancy complications, such as preeclampsia, preterm labor, and growth restriction.ĬfDNA has the benefit of being able to be done sooner in pregnancy, often as early as 10 weeks. However, traditional screening can assess for conditions that would not be found with cfDNA screening, such as open neural tube defects (ONTDs). cfDNA may also potentially screen for more chromosome conditions than traditional testing. There are pros and cons to both cfDNA screening and traditional screening, such as first trimester screening, second trimester screening, sequential screening, and ultrasound.įor some conditions, particularly Down syndrome, cfDNA has been shown to be a more accurate screening test than traditional screening tests. ![]()
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