The glucose tolerance test is used to detect abnormalities in glucose metabolism and is used to screen for diabetes mellitus, gestational diabetes mellitus and people at high risk of diabetes mellitus. For fasting blood glucose above 6.1mmol/L and random blood glucose above 7.8mmol/L need to be tested for glucose tolerance test. The glucose tolerance test needs to be performed after fasting and needs to be performed for three hours. During the test, it is not possible to do strenuous exercise, eat or drink stimulating food so as not to affect the results of blood glucose monitoring, and stop taking medications that have an effect on glucose tolerance, such as diuretics, birth control pills, etc., one week before the glucose tolerance test is performed. The specific method of glucose tolerance test is to draw blood to check the fasting blood glucose in the fasting state, take glucose solution containing 75g of glucose orally at one time after drawing blood, and then draw blood to check the blood glucose level in one hour, two hours and three hours respectively.