Both 4D ultrasound and B-ultrasound are a kind of ultrasound examination. Simple B-ultrasound is the most basic and simple ultrasound examination method, and its scope of application is relatively narrow. Ultrasound is the most basic and simple ultrasound examination method, and its scope of application is relatively narrow. On the other hand, color ultrasound examination is based on the ordinary ultrasound examination, and adds the examination of blood flow supply to the lesion. Four-dimensional ultrasound examination is a kind of color ultrasound examination, which is based on two-dimensional ultrasound examination with increased latitudinal changes. The examination results are more visual and clear, and can be recorded on a CD. In obstetrics and gynecology, simple ultrasound examination can be used for the diagnosis of gynecological diseases such as uterine fibroids, ovarian cysts and pelvic effusion, as well as for the examination of basic fetal development. In addition to these basic examinations, 4D ultrasound examination can be used mainly for the screening of fetal development, which is a very important examination during pregnancy.