The clinical significance of the ultrasound examination is related to the degree of dilatation and the specific week of gestation at the time of examination. Generally speaking, the dilatation of the intestinal canal does not exceed 7 mm in early and mid pregnancy and 25 mm in late pregnancy; if the dilatation of the intestinal canal is within the normal range, it is a physiological phenomenon, mainly related to the swallowing of amniotic fluid by the fetus, which is temporary and will return to normal after an interval of about 1-2 weeks; if the dilatation exceeds the normal value, it indicates that the fetal digestive system may If the dilatation range exceeds the normal value, it indicates that the fetus may have abnormalities in the digestive system, such as congenital megacolon, anal atresia, etc. Further examination is needed to confirm the diagnosis, and chromosomal examination will be done if necessary, and in more serious cases, termination of pregnancy may be considered, while in mild cases, no special treatment is needed.