Screening for gestational diabetes is generally recommended between 24 to 28 weeks of pregnancy, using a 75g glucose tolerance test to measure fasting blood glucose, blood glucose one hour after consuming glucose, and blood glucose two hours after consuming glucose. However, for pregnant women with high-risk factors, it is recommended to screen for blood glucose at their first prenatal visit. High-risk factors include women with a history of gestational diabetes, a history of delivering a large baby, obesity or polycystic ovary syndrome, those with a first-degree relative with a history of diabetes, positive fasting blood glucose or urinary glucose in early pregnancy, those who have had multiple unexplained miscarriages, fetal malformation, stillbirth history, and women who have given birth to newborns with respiratory distress syndrome. These women should all be screened for blood glucose at their first prenatal visit.