The fetus always moves on the right side during pregnancy, which is related to the fetal position. Because the fetus will stretch its arms and legs in the uterine cavity, in the process of stretching its arms and legs, pregnant women tend to feel more frequent fetal movements. Because the movement of the limbs is more obvious, the right side of the fetal movement is more frequent, indicating that this side is the limb. On the contrary, the left side belongs to the back, because the back activity will not be too obvious, so can not feel. In general, the fetal movement should be kept between 4-6 times per hour, which is within the normal range. As long as the fetal movement is regular and the rhythm does not change much, it means that the fetal development is normal and there is no need to worry too much. If the number of fetal movements is less than 4 times/hour or more than 6 times/hour, it means that it is not normal performance, and you should observe the condition of the fetus in time and continue to review. The fetal movement or fetal heartbeat is usually abnormal when the fetus is suffering from intrauterine ischemia and hypoxia.