If high blood sugar during pregnancy is diagnosed as gestational diabetes, fasting blood sugar greater than 5.8mmol/L or two hours after meal greater than 6.7mmol/L after regular dietary control is recommended to use insulin therapy under the guidance of a doctor. Gestational diabetes mellitus patients need to do a good job of dietary management, such as balanced distribution of carbohydrates, fats and proteins, to maintain a low-sugar, low-fat diet; exercise therapy, such as half an hour after meals, moderate aerobic exercise, such as walking, and so on. If the patient’s fasting blood glucose is greater than 5.8mmol/L after regular dietary control or the blood glucose two hours after meal is greater than 6.7mmol/L, or after dietary adjustment can appear urinary ketones and so on, it is recommended to use insulin therapy. Patients with gestational diabetes who are not sure if they need to take insulin can go to the hospital and consult a specialist.