What does non-invasive DNA testing check for?

Non-invasive DNA testing, also known as non-invasive prenatal DNA testing, is a new type of prenatal screening technology that analyzes fetal genetic information by drawing blood from the pregnant woman. This test primarily detects fetal chromosomal number abnormalities, such as: Trisomy 21, also known as Down syndrome, which checks for the risk of abnormalities in chromosome 21 that may lead to gonadal dysfunction, intellectual disability, and other conditions; Trisomy 18, also known as Edwards syndrome, which detects whether the fetus has an extra chromosome, potentially causing developmental delays, heart defects, and other problems; Trisomy 13, also known as Patau syndrome, which checks for the presence of an additional chromosome 13, associated with symptoms such as fetal intellectual disability and genital malformations.

Compared with invasive prenatal diagnostic methods such as amniocentesis and chorionic villus sampling, non-invasive DNA testing offers advantages of safety, accuracy, and early detection, avoiding risks such as miscarriage.

Non-invasive DNA testing is generally performed after the 10th week of pregnancy, when the concentration of fetal cell-free DNA in the blood is relatively high.