The accuracy of four-dimensional ultrasound for prenatal diagnosis of the fetus, compared with other periods of ultrasound, four-dimensional ultrasound has the highest accuracy rate. The diagnosis of color ultrasound generally does not say the accuracy rate, because the diagnosis of color ultrasound is only an auxiliary examination of the disease, many diseases are not based on the results of the color ultrasound examination, color ultrasound is just to see the things described down, and the clinician and then according to the patient’s clinical manifestations as well as some other examination results, the comprehensive to make a diagnosis of the disease, there is no disease is based on the color ultrasound examination results to No disease can be diagnosed directly based on the results of color ultrasound, so there is no accuracy rate. For example, in the human body tissue and organs found abnormal occupation, color ultrasound is able to describe its size, shape, internal structure and other manifestations, will suggest that there may be what disease, but a clear diagnosis or to the abnormal tissue cut down to do pathological examination to determine. Four-dimensional color ultrasound in the clinical application range is also very wide, but for the public is familiar with is to do prenatal screening of the fetus. Clinical four-dimensional ultrasound screening on the ultrasound doctor and ultrasound machine have high requirements, and the screening items are also more, it should be said that in all the prenatal ultrasound examination of the fetus is the most comprehensive, the accuracy rate is relatively high examination.