Riding a motorcycle at 12 weeks pregnant and simply hurting your knee after a fall will not usually affect the fetus. If there are symptoms such as vaginal bleeding and abdominal pain after an abdominal collision, the fetus will be affected. If you are 12 weeks pregnant and ride a motorcycle, and your knee is injured after a fall, you should observe whether your knee is limited in movement, but it is not a big impact if it is only a skin injury. If the fracture may have to be surgically repositioned and fixed, medication, regular treatment under the guidance of a doctor, the impact on the fetus is also relatively small. 12 weeks pregnant riding a motorcycle, fell and hurt his knee accompanied by abdominal collision, with vaginal bleeding, abdominal pain and other symptoms to be alert to fetal miscarriage, this situation will have an impact on the fetus, the need to consult a doctor in a timely manner. 12 weeks pregnant riding a motorcycle fell, with or without abdominal impact should go to the hospital for examination, to be able to accurately determine whether there is no effect on the fetus.