The typical symptoms of gestational diabetes are three more and one less, that is, drinking more, eating more and urinating more. However, in clinical practice most diabetic mothers do not have obvious symptoms of three more and one less. Some show recurrent episodes of vulvovaginal pseudomonal yeast infection, i.e. mycosis fungoides; some show excessive amniotic fluid in the baby; some show a fetus that exceeds the standard for the same gestational age, i.e. a huge fetus. The diagnosis of gestational diabetes is usually as follows: 1. Any pregnant woman with a family history of diabetes, weight >90kg before pregnancy, who has had polycystic ovary syndrome, a history of unexplained miscarriage, stillbirth, a history of delivering a huge baby or malformed fetus and other above conditions and the fetus in this pregnancy is large and the amniotic fluid is high, should be alert to the occurrence of combined gestational diabetes; 2. If the pregnant woman has high-risk factors, at If the fasting blood glucose exceeds 5.1mmol/L, gestational diabetes can be diagnosed; 3. If the fasting blood glucose is normal, further glucose tolerance test is needed, that is, fasting blood glucose plus 1 hour and 2 hours blood glucose test after taking sugar, as long as one of the three time points exceeds the standard, gestational diabetes can be diagnosed. Gestational diabetes can have adverse effects on both mother and child. If gestational diabetes is diagnosed, it is important to monitor and treat it from diet, exercise and medication to stabilize blood sugar to avoid further complications.