The most obvious symptoms of children with Down’s syndrome are special facial features and mental retardation, now briefly take you to understand: 1, the eyes are wider than the distance between the eyes; 2, the nose is a flat nose, the outer corner of the eye is raised upward, easy to have inner canthus; ear position than normal, the lower part is smaller than normal outer ear; 3, the mouth is short and fat tongue, can not be completely collected in the mouth, so constantly The back of the head is flattened, and the whole head is smaller and shorter than normal; the neck is also slightly shorter; the teeth grow slowly and are easily misaligned and uneven; the body looks shorter because the limbs are shorter; the fingers are fat and thicker, and the thumb and index finger are farther apart, so you can see the through palm and straw shoe foot. Motor development and sexual development are slower than normal children. 7. Intelligence is lower than normal. This is one of the most obvious characteristics of children with Down’s syndrome, with IQ generally ranging from 20 to 50, and gradually becoming more pronounced with age. 8. Easily combined with congenital heart disease. 9. Low immune function, prone to various infections, and more prone to leukemia than normal people. Pregnant women with positive Down’s syndrome screening results must undergo amniocentesis and do fetal cell chromosome examination to clearly diagnose whether they are Down’s children, thus avoiding the birth of Down’s children and greatly reducing the birth of deformed children.