The 4D ultrasound can see the baby’s appearance. At 24 weeks of pregnancy, the 4D ultrasound can clearly see the state of the baby’s eyes, nose, mouth and jaw, and also see the dynamic activities of the baby, so the 4D ultrasound during pregnancy can rule out congenital fetal malformations, mainly to determine whether the fetus has congenital developmental abnormalities, including whether the fetus has cleft lip and palate, hydrocephalus, spinal fracture, anencephaly, microcephaly or hydrocephalus, brain bulge, It can also determine whether there is any abnormality in the intestinal tract. If the fetus has poorly developed belly button, intestinal atresia, visceral ectopia, giant colon or digestive system problems, hydronephrosis, urinary tract obstruction, heart malformation and limb malformation during the formation process, it can be accurately judged and distinguished.