An ultrasound at 34 weeks of pregnancy showing a foot prelude is somewhat dangerous. It may prolong the labor process leading to fetal hypoxia, and may also lead to hemorrhage affecting the subsequent pregnancy. Foot pre-disposition is a manifestation of fetal malposition, if 34 weeks pregnant ultrasound shows foot pre-disposition, pregnant women may be a certain danger, easy to lead to prolonged labor, may also lead to fetal hypoxia, thus threatening the life of the fetus. In addition, preeclampsia may also cause the fetus to be unable to be delivered normally, and if the fetus is delivered compulsorily, it may also lead to hemorrhage, and both the pregnant woman and the fetus will be in some danger. If the bleeding is heavy, the damage to the uterus will be aggravated, which may affect the subsequent pregnancy and lead to infertility. Ultrasound at 34 weeks of pregnancy shows that preterm labor may not be accomplished through normal delivery, so it is recommended that the pregnant woman should follow the doctor’s instructions to have checkups on time and also listen to the doctor’s advice on choosing the appropriate mode of delivery, so as to avoid affecting both the mother and the fetus.