Pregnant women undergo an oral glucose tolerance test at 24-28 weeks, and a diagnosis of gestational diabetes mellitus is considered if the 2-hour postprandial blood glucose is ≥8.5 mmol/L. Therefore, pregnant women with 2-hour postprandial blood glucose 8.9mmol/L considered gestational diabetes, is more serious and may cause adverse effects on the pregnant woman, fetus and newborn. 1. Impact on pregnant women: diabetes will increase the incidence of spontaneous abortion in early pregnancy, easy to combine with hypertensive disorders in pregnancy, will reduce the resistance of pregnant women, easy to combine with infections and so on. 2. Impact on the fetus: High blood glucose environment in early pregnancy is a high risk factor for fetal malformation, increasing the possibility of macrosomia, which can also lead to fetal growth restriction. 3. Impact on the newborn: maternal hyperglycemia will reduce the production of fetal lung surface active substances, resulting in neonatal respiratory distress syndrome; prone to neonatal hypoglycemia. Hyperglycemia endangers the mother as well as involves the fetus and the newborn. Therefore, if you have gestational diabetes, you should go to the hospital and be treated under the guidance of a doctor.