What is the Down syndrome screening test?
Jul 08, 2025
Source: Cainiu Health
Dr. Zhou Xiaofeng
Introduction
Under normal circumstances, Down syndrome screening, officially known as prenatal screening for Down syndrome, is an important method of assessing the risk of specific genetic disorders in the fetus during pregnancy. It is important to note that pregnant women who have passed the optimal screening time window should be cautious, as screening too early or too late may affect the accuracy of the results. During the test, pregnant women should maintain a calm and relaxed mindset.
Generally, Down syndrome screening, officially known as prenatal screening for Down syndrome, is an important method of assessing the risk of specific genetic disorders in the fetus during pregnancy. Detailed analysis is as follows:
Down syndrome screening is an essential prenatal screening test during pregnancy. Its main purpose is to calculate the risk probability of the fetus suffering from Down syndrome, Edwards syndrome, and open neural tube defects by testing indicators such as maternal serum alpha-fetoprotein, human chorionic gonadotropin, and unconjugated estriol, combined with the mother's age, gestational age, weight, and other factors. This test is usually performed between 15 to 20 weeks of pregnancy. It is non-invasive, simple to perform, and relatively safe. However, it is only a screening method and cannot provide a definitive diagnosis. If the result indicates high risk or borderline risk, further diagnostic tests such as amniocentesis or non-invasive DNA testing are required.
It should be noted that pregnant women who have passed the optimal screening window should be cautious, as screening too early or too late may affect the accuracy of the results. During the test, pregnant women should maintain a calm mindset and avoid excessive anxiety even if the screening result indicates high risk, as further diagnostic testing will still be needed.
