The methods of predicting fetal weight are ultrasound, uterine height and abdominal circumference, etc., as follows: 1. Ultrasound: measure the fetal biparietal diameter, head circumference, abdominal circumference, femur length and other indicators under ultrasound, and use the calculation formula to roughly assess the weight of the fetus, or you can estimate directly under ultrasound based on the volume of the fetus; 2. Uterine height and abdominal circumference: the fetal weight can be calculated in late pregnancy based on the uterine height and abdominal circumference, and the common formula is fetal weight ( g) = uterine height (cm) × abdominal circumference (cm) + 200, if the pregnant woman’s fetal membranes have ruptured, it is plus 500, this calculation is applicable to pregnant women who are in full-term labor. However, it should be noted that the above methods are subject to certain errors, if the pregnant woman has thick abdominal fat, the fetal position is not allowed, the measurement error will be larger, the specific to the fetal birth weight as the standard, generally speaking, the actual weight at birth and the predicted weight will be about ± 10% error. During pregnancy, you should pay attention to nutritious diet and not overeat. In the middle of pregnancy, you can assess whether the fetus has growth restriction according to the fetal weight, and if there is fetal growth restriction, it must be examined and treated in time. It is recommended to control the diet in the late pregnancy to avoid fetal stunting or overweight.