Pregnant women with inaccurate menstruation before pregnancy, early implantation of the fertilized egg, and incorrect projection of the gestational week may result in a fetus larger than the gestational week, which is usually not obviously harmful, and requires regular obstetric examination, combined with ultrasound results to deduce the correct gestational week. If the week of pregnancy is correctly estimated, and the ultrasound shows that the fetus is larger than the gestational week, the probability of difficult labor during delivery will increase. In early pregnancy the fetus is larger than the gestational week, often due to the effect of high blood glucose levels, which will increase the probability of fetal limb and bone dysplasia, malformation, intrauterine distress, and will also increase the risk of miscarriage, in addition to the incidence of heart disease in pregnancy and high blood pressure in pregnancy. Pregnant women should strictly limit the intake of high-calorie foods and supply them as needed, as well as strengthen regular exercise to control fetal weight so as not to overgrow the fetus and observe fetal development during regular checkups. Poor control of fetal weight in late pregnancy may result in the formation of a large child, which increases the risk of difficult labor, perineal tear, and postoperative infections; the chances of the newborn suffering from hypoglycemia, hypocalcemia, and pulmonary atelectasis will also be increased, and in the case of a more serious situation, the doctor can determine whether it is necessary to choose cesarean section to terminate the pregnancy.