Glucose tolerance testing can be done at 23 weeks, but a 75g oral glucose tolerance test is recommended at 24-28 weeks of pregnancy, and at the first visit after 28 weeks. A 75g oral glucose tolerance test (75g OGTT) is generally recommended for pregnant women who have not yet been diagnosed with pre-pregnancy diabetes or gestational diabetes at the 24th to 28th week of pregnancy, and at the first visit after 28 weeks. glucose tolerance testing is available at 23 weeks, and early intervention can be performed if the test is positive, but re-testing is recommended at a later stage if the result is negative. In the middle and late stages of pregnancy (after 14 weeks), with the increase of gestational weeks, pregnant women’s body will increase the antagonism of insulin-like substances, such as tumor necrosis factor, etc., so that pregnant women’s sensitivity to insulin gradually decreases, and at this time, if insulin secretion is limited, it is easy to develop gestational diabetes. Therefore, it is recommended that glucose tolerance test should be conducted at the recommended time period, and at the same time, a healthy and reasonable diet should be taken during pregnancy to increase the intake of nutritious food and moderate exercise in order to prevent the occurrence of pregnancy complications.