Читать книгу Protocols for High-Risk Pregnancies - Группа авторов - Страница 50

Risk assessment for fetal trisomy 21 for many years involved primarily second‐trimester serum screening with maternal serum assay of alphafetoprotein (AFP), hCG, unconjugated estriol (uE3), and inhibin‐A (quad marker screening). In some practices, ultrasound assessment of features of aneuploidy, such as characteristic malformations or minor findings or markers, was used to assess or modify risk. Second‐trimester serum screening is now less commonly used due to the higher detection of first‐trimester combined or cfDNA screening, as well as the benefits of earlier detection. However, there is still a role for quad marker screening in patients who do not present for care until the second trimester.