You need to make an appointment in advance for the 4D ultrasound, and also pay attention to the examination time, and you can also move appropriately when doing 4D, which is beneficial to the examination. Also pay attention to wear loose clothing. 4D ultrasound is usually performed at 20-24 weeks of pregnancy, but pregnant women need to make an appointment in advance. Many hospitals need to make appointments for 4D ultrasound a long time in advance, so when it’s almost time for 4D, you need to go to the hospital for consultation to avoid missing the time. You don’t need to have an empty stomach or hold your urine during the 4D ultrasound. So pregnant women can eat enough to do it, so as not to wait too long for hypoglycemia. It is better for pregnant women to wear loose and easy-to-examine clothes for 4D ultrasound, which is more convenient. The doctor needs to look carefully at the development of the fetus during the examination to see if there are any problems, so the examination time is longer. If the baby’s position is not good during the examination and you cannot see the details of the face, you can move around and do the examination again.