35 weeks pregnant, the normal range of fetal head circumference in the 293-330mm, the standard value is 312mm, specific varies from person to person, through the head circumference can effectively determine fetal development: such as the existence of abnormal head circumference, first need to be combined with the menstrual situation and the results of the ultrasound of the early pregnancy, check the gestational week, review the medical records, to determine the week of the fetus appeared to be head circumference and growth rate, combined with the biparietal radius, abdominal periphery and the length of the femur Simple biparietal diameter and head circumference are abnormal, and the abdominal circumference and femur length are normal: at 35 weeks of pregnancy, the fetal biparietal diameter and head circumference are large and increasing, and the abdominal circumference is normal or small, except for abnormal development of craniocerebral structures, such as hydrocephalus, etc., and it is necessary to go to prenatal diagnostic institutions for consultation and counseling, so as to exclude the hydrocephalus and other conditions; if the fetal biparietal diameter and head circumference are small, and the development is slow, it is not except for abnormal craniocerebral development, and it is not necessary to go to prenatal diagnostic institutions to consult and rule out hydrocephalus. If the fetal biparietal diameter and head circumference are small and the development is slow, not excepting craniocerebral development abnormality, it is necessary to carry out fetal craniocerebral nuclear magnetic detection of fetal craniocerebral development, and it is necessary to go to the prenatal diagnostic institution for consultation and counseling, to exclude the abnormalities of craniocerebral development; 2, the biparietal diameter, the head circumference, abdominal circumference, and the length of the femur are small: not excepting fetal growth retardation, and after checking the week of gestation, it is necessary to screen for the causes of fetal growth retardation, such as chromosomal abnormalities of the fetus, infections, maternal hypertension, diabetes, Heart disease, abnormal nail function, immune disease, easy to embolism, etc., deal with the original disease at the same time to give nutritional supportive treatment; can be appropriate to increase the vitamin and protein-rich foods, such as spinach, celery, milk, eggs, etc., to replenish the human body’s lack of nutrients, conducive to the growth of the fetus; 3, the biparietal diameter, head circumference, abdominal circumference, femur length are too big: the fetus is too big with genetic factors related to the need to combine with the parents’ body size and the weight of the fetus of the previous delivery comprehensive judgment. In addition to genetic factors, we should consider the over-nutrition of pregnant women or the existence of gestational diabetes mellitus, especially women with excessive amniotic fluid and recurrent mycosis vaginalis, even if the results of glucose tolerance are normal, we should review the blood glucose situation to rule out the large fetus caused by hyperglycemia; in addition to this, pregnant women should go to the nutrition clinic during pregnancy to receive standardized dietary guidance, eat separate meals and avoid eating too much high-calorie food. In addition, pregnant women should go to the pregnancy nutrition clinic to receive standardized dietary guidance, eat separate meals, avoid eating too much high-calorie foods, such as sugary foods and fruits, and control fetal weight gain by combining moderate exercise. In the second trimester of pregnancy, the fetus changes rapidly, and it is necessary to strengthen the obstetric examination, pay attention to the fetal movement, and go to the hospital in time if there is any abnormal fetal movement.