You need to choose the best time for the 4D ultrasound, make an appointment in advance and have breakfast in order to pass it more quickly, but you don’t need to be anxious if you don’t pass it at once. 1. Choose the best time: when a woman is 22-26 weeks pregnant, the amount of amniotic fluid will be more, and the development of the fetus is also more comprehensive, when the four-dimensional ultrasound examination, it will be relatively clear. 2. Make an appointment in advance: It is best to make an appointment in advance for 4D ultrasound to prevent queuing up at the hospital from causing the pregnant woman to strain herself and affecting the results of the examination. 3. Eat breakfast: do four-dimensional color ultrasound does not need fasting, you can eat breakfast after going to do, so that the fetus in the abdomen of the greater mobility, help comprehensive observation. The four-dimensional ultrasound is not through once don’t be anxious, follow the doctor’s advice to choose another time to do it can be.