The normal fasting blood glucose value for pregnant women should be less than 5.1 mmol/L. During pregnancy, obstetricians usually perform routine glucose tolerance screening, which involves pregnant women taking 75 g of glucose orally and then drawing blood for blood glucose testing on an empty stomach, at 1 hour and at 2 hours. If one of the three blood glucose measurements is abnormal, gestational diabetes is diagnosed. If a pregnant woman has abnormal blood glucose during the glucose tolerance test, or if she meets the criteria for gestational diabetes, she should consult a nutritionist to develop a healthy diet for the pregnancy and exercise appropriately after meals. If the blood glucose control is still unsatisfactory after diet and exercise, insulin treatment is needed because oral hypoglycemic drugs cannot be used during pregnancy.