Pregnant women with fasting blood sugar 5.8mmol/L may cause abnormal fetal development or cause the fetus to develop heart malformation. Normal fasting blood sugar of pregnant women is 3.3mmol/L-5.3mmol/L, when the blood sugar is lower than 3.3mmol/L, it is considered hypoglycemia, and fasting blood sugar 5.8mmol/L is a little bit high. Generally there will not be any effect, but in the case of deviation of blood sugar should be timely to the hospital for examination. If the blood sugar is elevated during early pregnancy, it is necessary to control the diet structure appropriately, and do glucose tolerance test at 22-24 weeks of pregnancy to determine whether there is gestational diabetes, and then do further treatment. Pregnant women in a state of high blood sugar levels, can lead to fetal overgrowth, may lead to the emergence of giant fetus, and if long-term blood sugar after the elevation, will stimulate the placenta’s capillary proliferation, leading to insufficient perfusion of the placenta, in the middle and late stages of pregnancy, there will be fetal distress. If the blood sugar level is too high in early pregnancy, it will affect the growth and development of the embryo, and cause some malformations in the development of the fetus, or cause the development of the embryo to stop, miscarriage, mainly for the development of the fetus, mainly for the development of malformations in the development of the heart and the nervous system can be caused by some anomalies. Therefore, during pregnancy, you should have regular checkups to avoid any impact on the development of the fetus.