4D ultrasound does not require an empty stomach. 4D ultrasound is used to rule out fetal malformations. It is generally through the 4D ultrasound examination, you can check the fetus heart, limbs, face and other multiple malformations and other conditions. It is best to go to a regular large hospital for the examination, so that the examination is more accurate. The time of 4D ultrasound examination is 24-26 weeks of pregnancy, and it is best to pay attention to rest in the middle of pregnancy. It is also recommended to eat more nutty foods, such as drinking more walnuts and eating pine nuts, and fresh fruits and vegetables such as cucumbers, tomatoes, apples and bananas, which help the baby develop. It is better not to stay up late during pregnancy and not to eat spicy and stimulating food. It is also recommended not to be exposed to things that have radiation to avoid causing fetal malformations, etc.