Under normal circumstances, the normal value of fetal abdominal circumference at 20 weeks of pregnancy is between 12.7-17.7cm, with a mean value of 15.2cm. The abdominal circumference of pregnant women is between 76-89cm, but each pregnant woman’s body shape is different and there is no absolute uniform standard. The value of fetal abdominal circumference can reflect the development of the fetus to some extent. A large fetal abdominal circumference indicates a fat fetus, and a small fetal abdominal circumference indicates a small fetus. However, it usually cannot be used as a single indicator, and it is recommended to go to a regular hospital for a checkup to determine whether the fetus is developing normally through the results of a comprehensive examination. The abdominal circumference of a pregnant woman grows fastest at 20-24 weeks of gestation, measured in the standing position (supine), with the navel prevailing, and horizontally around the abdomen for one week. The abdominal circumference measured at 16 weeks of gestation is used as the base, and the growth value is kept at about 21 cm until full term. During pregnancy, we should pay attention to balanced nutrition, reasonable diet, avoid eating too much high-calorie food, excess nutrition can lead to excessive growth of abdominal circumference, the fetus is too large, gestational hypertension, gestational diabetes and other conditions.