Mid-pregnancy pain in the inner thigh root, this situation is mainly due to the process of pregnancy, the thigh hip joint position continues to maintain the state of abduction, external rotation, the inner thigh root muscles, tendons, ligaments and other soft tissues will be in a constant state of tension. As the tension is too long, it will form localized strain, and gradually form aseptic inflammatory lesions, and the inflammatory metabolic products will stimulate the peripheral nerves, and then the pain will appear. In addition, the patient is often combined with the cold, because the cold will lead to muscle tissue becomes more tense, arterial blood supply appears to decline, the local electrolyte, energy and nutritional support decreases, which will aggravate the pain. In addition, due to the slowing down of venous return, the slowing down of blood circulation leads to the production of inflammatory metabolites can not be metabolized in a timely and effective manner, the formation of inflammatory buildup will lead to inflammatory edema, stimulation of the peripheral nerves will also lead to pain.