Fetal biparietal diameter of 8.6cm and head circumference of 30.7cm at 38 weeks of pregnancy are small and generally abnormal, suggesting fetal growth restriction. The normal value of fetal biparietal diameter at 38 weeks of gestation is 8.8-10.4cm, and the normal value of head circumference is 30.8-35.8cm. fetal head circumference and biparietal diameter are lower than normal values, which suggests fetal growth restriction, and the causes of fetal growth restriction include insufficient nutritional supply from the mother, gestational hypertension, and placental transit disorder, etc. The cause of fetal growth restriction should be actively searched for, improving placental circulation, and improving placental circulation. The causes of fetal growth restriction include insufficient nutritional supply of the mother, gestational hypertension, placental transport disorders, etc. The cause of fetal growth restriction should be actively searched for, the placental circulation should be improved, and fetal detection should be enhanced. If fetal growth restriction occurs, one should go to the hospital in time for treatment under doctor’s guidance and terminate the pregnancy if necessary.