It is common to have a glucose tolerance test done at about 28 weeks of pregnancy, which is also known as glucose screening, and is actually an OGTT test, mainly to rule out the presence of gestational diabetes. Therefore, there is no difference between glucose screening and glucose tolerance, just a difference in terminology. Generally, at 28 weeks of pregnancy, the doctor will recommend that the pregnant woman go to the hospital for a glucose tolerance test, first to draw blood on an empty stomach to check fasting blood sugar, and then to drink 75 grams of hypertonic glucose after the blood draw, and then to draw blood one hour and two hours after drinking the sugar water to check the one-hour blood sugar and two-hour blood sugar respectively, according to the three blood sugar situations We will determine the presence or absence of gestational diabetes based on the three blood glucose levels. Under normal circumstances, fasting blood sugar is less than 5.1, one-hour blood sugar is less than 10.0, and two-hour blood sugar is less than 8.5. If any one of the three is greater than the normal value, gestational diabetes can be diagnosed. At this time, it is necessary to control the diet and change the diet to reduce blood sugar, because high blood sugar often affects the growth and development of the fetus, and even leads to immature fetal lungs, and may also cause the appearance of a huge baby. This is why blood sugar is especially important for both the pregnant woman and the fetus, which is why it needs to be strictly checked and controlled. If you have gestational diabetes, you often cannot consume too much food containing sugar, and you should eat as little fruit as possible, and you must eat more fresh vegetables and mixed food.