Large biparietal diameter may be related to the development of the fetus itself or gestational diabetes mellitus, in which case dietary intake of high-calorie foods should be avoided. 1. Fetal growth: To prevent the occurrence of macrosomia, pregnant women with large biparietal diameter are advised to go to the hospital for fetal ultrasonography to estimate the weight of the fetus. Once it is determined that the fetal weight is higher than the average value of the same gestational week, it is recommended to inhibit the rate of fetal weight gain by controlling the diet, strictly controlling the intake of high-calorie foods, and at the same time eating more vegetables and high-protein foods, such as fish, shrimp, beef and other foods. 2. Pregnant women with gestational diabetes: It is recommended that pregnant women go to the hospital for a glucose tolerance test when they are 24-28 weeks pregnant. Pregnant women with gestational diabetes, you need to strictly control the calorie intake in the diet according to the standard of gestational diabetes, and at the same time to strengthen the exercise after meals. Once the blood glucose control is not up to standard, you need to go to the hospital in time to seek medical treatment.