Pregnant women do not control sugar, prone to gestational diabetes, the impact on the mother and the fetus is great, pregnant women may develop high blood sugar, susceptible to infection, gestational hypertension and other diseases, but also cause a series of complications such as macrosomia, fetal malformations, miscarriage, preterm labor and so on. Pregnant women who do not control sugar and have higher blood sugar may suffer from hyperglycemia, susceptibility to infection, gestational hypertension and other diseases, and in severe cases, diabetic ketoacidosis, which will have an impact on the well-being of the pregnant woman. Fetus in a long-term high blood sugar environment, will lead to the emergence of huge children, causing fetal malformation or even the consequences of abortion. Pregnant women must control the intake of sugar during pregnancy, reduce the amount of sugar intake in time when high blood sugar occurs, and have regular checkups to check blood sugar, and if there is any abnormality, it should be controlled and treated according to the doctor’s instructions.