According to the 2013 WHO publication “Diagnostic Criteria and Classification of Newly Diagnosed Hyperglycemia in Pregnancy”, hyperglycemia that occurs during pregnancy is divided into two categories: one is the combination of pregnancy after the diagnosis of diabetes mellitus called “Diabetes mellitus in pregnancy”; the other is the first occurrence or detection of diabetes mellitus during pregnancy called “Gestational diabetes mellitus”. The other category is diabetes mellitus in pregnancy, which occurs or is detected for the first time during pregnancy. Diagnostic criteria: Every pregnant woman should have a 75g OGTT at 24-28 weeks of gestation to measure her blood glucose. The diagnostic criteria for diabetes mellitus during pregnancy are the same as those for diabetes mellitus in the non-pregnant population, i.e. fasting blood glucose ≥ 7.0 mmol/L,or OGTT2h blood glucose ≥ 11.1 mmol/L. Diagnostic criteria for gestational diabetes mellitus: 75g of oral glucose, fasting blood glucose ≥ 5.1 mmol/L, 1 hour after taking sugar blood glucose ≥ 10.0 mmol/L, 2 hours after taking sugar blood glucose ≥ 8.5 mmol/L, more than one time point higher than the above criteria can be diagnosed. Management of gestational diabetes: 1. Early diagnosis and standardized management. 2. Targeted diabetes education. Individualized diet to ensure energy requirements of the pregnant woman and fetus. Choose carbohydrates with low glycemic index as much as possible. For those who use insulin, choose the type and amount of carbohydrates according to the dosage and form of insulin. It can be 5-6 meals per day. 3. Avoid using oral hypoglycemic drugs, and choose insulin therapy if blood sugar cannot be controlled by diet management. (Endocrinology) 4. Management target: preprandial blood sugar 3.3-5.3mmol/L, 1 hour postprandial blood sugar ≤7.8mml/L, 2 hours postprandial blood sugar ≤6.7mml/L, glycated hemoglobin below 6%. 5. Those with combined hypertension should avoid the use of ACEI, ARB, ? receptor blockers and diuretics. Strictly control blood pressure below 130/80mmHg. 6. Strengthen self-monitoring of blood glucose. Blood lipid, liver and kidney function, glycosylated hemoglobin, routine blood and urine, fundus examination should be performed once every three months. 7. Strengthen the monitoring of fetal development. (Obstetrics and Gynecology) 8. Mode of delivery: Diabetes is not an indication for caesarean section, and vaginal delivery is allowed without special circumstances. 9. Those with normal blood glucose after delivery should be re-evaluated with 75g OGTT at 6 weeks and followed up for life.