The cost of a 4D ultrasound generally ranges from about $250 to $350 for a level II hospital exam and from about $350 to $450 for a level III hospital exam. It depends on the level of the local hospital. Four-dimensional color ultrasound compared to two-dimensional, three-dimensional ultrasound can be more dynamic, three-dimensional observation of fetal structures, and at the same time can measure the local blood flow, such as umbilical cord blood flow, middle cerebral artery blood flow and so on. Four-dimensional color ultrasound is mainly used to screen for fetal structural malformations during pregnancy, and it is generally recommended to have a four-dimensional ultrasound examination around the 24th week of pregnancy. Due to the different levels and nature of each hospital, the charges between hospitals are not completely uniform. For the cost of 4D ultrasound, it is generally around RMB 250~350 in a secondary hospital and around RMB 350~450 in a tertiary hospital, and you should consult the hospital for specific charges. If you have any other questions, it is recommended to consult a professional doctor for guidance.