Pregnancy is a special physiological process experienced by women, usually from conception to delivery, the whole process is 280 days, such as 28 days as a gestation month, the whole process is 10 gestation months or 40 weeks. Some of the hormones in a woman’s body change significantly during pregnancy. Diabetes mellitus is a common chronic metabolic disease, the incidence of which is currently around 10% in China. The age of onset of diabetes has a tendency to be younger, and it is not uncommon for young people aged 20-40 to have type 2 diabetes, in addition to a portion of type 1 diabetes patients. Many of these patients are facing the problem of marriage and childbirth. A proportion may be diagnosed with diabetes before pregnancy. The other portion discover diabetes or gestational diabetes mellitus (GDM) after pregnancy. Either the former or the latter hyperglycemia will have adverse effects on the pregnant woman and the fetus, which is something we need to be concerned about and intervene. Foreign data, the U.S. Centers for Disease Control and Prevention (CDC), a recent report that the prevalence of gestational diabetes mellitus (GDM) in the U.S. as high as 9.2%, there is no relevant data in China. Diabetes combined with pregnancy may also be more concerned about, not to go into detail here. But for some of the previous “no” diabetes pregnant women, what do we need to pay attention to after pregnancy? First of all, we need to know what are the common risk factors for gestational diabetes, such as whether there is a family history of diabetes, whether overweight and obesity, whether it is an advanced pregnancy, whether there is polycystic ovary syndrome (PCOS), and so on. This is because early detection and treatment is very favorable to the prognosis of the pregnant woman and the fetus. Briefly introduce the harm of gestational diabetes? It mainly includes 2 aspects: one is to pregnant women: they can develop hyperemesis gravidarum, placenta previa, and difficult labor. Another data shows that the risk of GDM developing into type 2 diabetes mellitus in the next 5 to 10 years is significantly elevated, i.e., GDM is very likely to become true type 2 diabetes mellitus. Therefore, GDM should be examined by OGTT at 6-12 weeks postpartum Secondly, for the fetus: there can be intrauterine developmental abnormalities, neonatal malformations, macrosomia, neonatal hypoglycemia, neonatal respiratory distress and so on. How to detect and diagnose GDM in time is a very real problem. Due to the different understanding of the changes in blood glucose of pregnant women during pregnancy and the limitations of evidence-based medicine, the diagnostic criteria for gestational diabetes mellitus are not exactly the same in different countries and international organizations, and are still debated. However, it is recommended that screening for diabetes should be performed during the labor and delivery examination, and the OGTT test with 75g glucose should be performed at 24-28 weeks of gestation if there is no diabetes. Currently, the diagnostic criteria for gestational diabetes in China are: 75g OGTT (glucose tolerance) test at 24-28 weeks of gestation for all pregnant women: fasting blood glucose R5.1mmol/L, R10mmol/L one hour after taking sugar, R8.5mmol/L two hours after taking sugar, and GDM can be diagnosed when the glucose of one point or more is higher than the above criteria. GDM blood glucose control target: fasting blood glucose Q5.3mmol/L, 2-hour postprandial blood glucose Q6.7mmol/L, glycated hemoglobin 6.0% or less Glycemic control target for preconception diabetes combined with pregnancy: preprandial, bedtime and nighttime blood glucose 3.3-5.4mmol/L, 2-hour postprandial blood glucose 5.4-7.1mmol/L, glycated hemoglobin <6.0%. The goals of pre-pregnancy glycemic control for diabetic patients preparing for pregnancy are: fasting blood glucose 3.9-6.5 mmol/L, 2-hour postprandial blood glucose Q8.5 mmol/L, and glycosylated hemoglobin 7.0% or less, preferably 6.5% or less.