Which of the following markers is used in prenatal screening for Down syndrome?

When screening for Down syndrome during prenatal care, a combination of several biomarkers is utilized to improve the accuracy of the screening. Alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and inhibin A are each important components of the multiple-marker screening tests.

Alpha-fetoprotein is a protein produced by the fetal liver, and abnormal levels can suggest the presence of chromosomal abnormalities, including Down syndrome. Human chorionic gonadotropin is a hormone produced during pregnancy, and elevated levels are often associated with increased risk for Down syndrome. Inhibin A is another hormone that is measured during pregnancy and is also associated with Down syndrome risk—higher levels can indicate an increased likelihood of this condition.

Using these three markers together in a combined screening test enhances the predictive ability for identifying pregnancies at increased risk for Down syndrome. Therefore, recognizing that all of these individual markers play a role in the screening process highlights the importance of a multifaceted approach to prenatal screening.