Whether glucose 6.39 mmol/L is diabetes or not needs to be clarified whether it is fasting blood glucose, random blood glucose or blood glucose after 2 hours of oral glucose tolerance test, and there are also different criteria for different groups of people. If it is a random blood glucose for people without previous diabetes, the diagnostic criteria for diabetes are not met; if it is a fasting blood glucose for pregnant women, gestational diabetes will be considered. 1. For people with no previous diabetes: diabetes is usually measured by a fasting blood glucose ≥7.0 mmol/L and a 2-hour glucose load ≥11.1. Diabetes mellitus is diagnosed if typical diabetic symptoms are also present. 2. For pregnant women: gestational diabetes mellitus is usually measured by fasting blood glucose ≥ 5.1 mmol/L and 2-hour glycemic load ≥ 8.5 mmol/L. For women with high risk factors such as obesity and family history of diabetes, they should pay particular attention to changes in blood glucose values. If the test blood glucose is abnormal, it is recommended to go to a regular hospital to avoid delay.