The weight of the fetus may affect the safety of delivery and the health of the fetus. Usually, the weight of the fetus at birth is controlled to be between 2,500 and 4,000 grams as the normal weight. As the physical condition of each pregnant woman is different, the growth and development of the fetus will also be different. If the weight of the fetus at the time of birth is low, less than 2,500g, it is easy for the fetus to develop abnormally, malnutrition, and feeding difficulties. If the weight of the fetus exceeds 4000g, it is called macrosomia in medicine, and macrosomia may significantly increase the chance of difficult labor, and due to the relatively slow progress of labor, mothers are prone to post-partum hemorrhage, and newborns are prone to respiratory difficulties and other symptoms, therefore, the birth weight of the fetus is controlled at 2,500-4,000 grams of weight is considered to be a normal weight. It is recommended that pregnant women should take obstetric examinations on time, pay attention to rest, eat a normal and reasonable diet, and do not need to strengthen the nutrition too much to avoid over-nutrition.