Gestational diabetes mellitus can be considered as gestational diabetes mellitus, regardless of whether it is treated with insulin or not and whether the blood sugar returns to normal after delivery. For the fetus, it can directly lead to miscarriage, intrauterine growth retardation, and an increased chance of malformation, giant fetus and low birth weight baby. Nearly half of the “sugar moms” may develop type 2 diabetes in the future, and their children are at greater risk of obesity, diabetes, hypertension, and coronary heart disease. Therefore, all pregnant women should be screened for diabetes at 24 to 28 weeks of gestation. For high-risk pregnant women who are over 35 years old, obese, have a family history of diabetes, and have a history of bad pregnancies and deliveries, they should also undergo a glucose tolerance test if needed for early detection and treatment.