Do Down screening has the following precautions: 1, do Down screening three days before normal exercise, diet, not reduce the number of carbohydrates, normal eating carbohydrates, the number of carbohydrates intake per day can not be less than 150g; 2, to carry out the Down screening of the day before the night do not eat, to ensure that the fasting for more than eight hours; 3, punctual in the time point of the test to arrive at the location, to do the Down screening needs 2-3 hours of time 4. If you choose 75g of anhydrous glucose powder for Down screening, it should be incorporated into 300ml of water, and venous blood should be drawn on an empty stomach as well as one hour, two hours and three hours after drinking it, and in the case of a pregnant woman, the blood collection only needs to be taken up to the second hour. If dextrose hydrate is chosen, 82.5g of dextrose hydrate is usually used. Don’t worry too much about elevated blood glucose levels, there are lifestyle interventions that can be done, such as controlling diet and exercising. Dietary advice is to eat a low-salt, low-fat, light diet, controlling the total calories, choosing to eat small, frequent meals, and to exercise, one hour after meals, preferably for more than 30 minutes, which can control blood glucose.