A glucose tolerance test is usually required if you have a high blood glucose 2 hours after a meal when your fasting blood glucose is normal, or if you are a pregnant woman, or if you have risk factors for diabetes. People with normal postprandial blood glucose, who are not pregnant, or who are not at risk for diabetes, may be exempted from glucose tolerance after evaluation by a physician. 1. High blood glucose 2 hours after meal: Although fasting blood glucose is normal, high blood glucose 2 hours after meal may be pre-diabetes or diabetes, and it is recommended to have a glucose tolerance test to clarify the diagnosis. 2. Pregnant women: Regardless of the results of blood glucose monitoring, it is recommended that a glucose tolerance test be performed to rule out the possibility of gestational diabetes mellitus. 3. Presence of risk factors for diabetes: such as a family history of diabetes, high BMI, cardiovascular disease, hypertension, hyperlipidemia, etc., a glucose tolerance test is recommended. It is recommended that people with abnormal blood glucose or at risk of diabetes seek timely medical attention.