It is very necessary if a pregnant woman has a 4D ultrasound before delivery. 4D ultrasound has a high resolution, and fetal detoxification examination through 4D ultrasound is one of the most important means of prenatal fetal detoxification. Pregnant women can have 1-2 4D ultrasound examinations during pregnancy to exclude the fetus and the mother’s own reasons, and can observe the growth and development of the fetus more clearly. It can also show the development of all organs of the fetus, the maturity of the placenta and the condition of the amniotic fluid, etc., so as to monitor the healthy growth of the fetus in real time.