The 4D ultrasound examination for pregnant women is mainly to check whether the fetus has any malformation. It screens the fetus’ head, face, spine and limbs for malformations; it screens the fetus’ chest and abdominal organs, including liver, spleen, gallbladder, kidney and bladder for malformations. Screen the fetal heart for malformations and exclude congenital heart diseases, such as single ventricle, single atrium, right heart hypoplasia, transposition of the great arteries, tetralogy of Fallot and other congenital heart malformations; exclude fetal cleft lip, cleft palate, limb defects and other diseases; also check the pregnant woman’s cervix and whether the placenta, umbilical cord, amniotic fluid and fetal appendages are normal.