Background trisomy risk refers to the risk of fetal chromosome abnormality. Among them, the most common chromosomal abnormality is Down syndrome (2 1 trisomy background syndrome). Others include 13 trisomy syndrome and 18 trisomy syndrome.
Background risk assessment of trisomy is helpful for families to make psychological and material preparations for fetal health. Knowing the risks in advance will help parents adjust their mentality more quickly in the face of fetal abnormalities and make appropriate plans for their children's future.