Gestational diabetes mellitus is a type of diabetes mellitus that occurs only during pregnancy. The majority of gestational diabetes mellitus has postpartum blood glucose that can return to normal, while some pregnant women are unable to return to normal postpartum. Due to the increase of antagonistic insulin-like substances in the body of pregnant women in the middle and late stages of pregnancy, the sensitivity of pregnant women to insulin decreases with the rise of gestational weeks, and for pregnant women with limited insulin secretion, it may be difficult to maintain the normal blood glucose level due to insufficient insulin secretion, which may lead to the elevation of blood glucose. Most of the pregnant women antagonize insulin-like substances in the body to reduce after delivery, and insulin sensitivity is restored after delivery, and blood glucose can be restored to normal level. However, some pregnant women can not return to normal levels of blood glucose even after pregnancy, and need to continue to use insulin, metformin and other hypoglycemic drugs for treatment. Therefore, pregnant women with gestational diabetes mellitus should also monitor their blood glucose level after delivery and use insulin treatment according to the doctor’s instruction. Patients whose blood glucose is still abnormal 6 weeks after delivery should go to the hospital in time to improve the examination, and then give targeted treatment in a timely manner after the diagnosis is clear.