Bleeding at 14 weeks of pregnancy may be caused by preeclampsia, placenta previa, cervical polyps and so on. 1. Pre-eclampsia: mainly manifested by a small amount of vaginal bleeding, accompanied by paroxysmal abdominal pain, ultrasound suggests that the development of the fetus is normal, combined with the history of the diagnosis can be assisted, you need to comply with the doctor’s instructions to maintain the fetus actively treatment. 2. Placenta hypoplasia: ultrasonography suggests that the position of the placenta is low, and vaginal bleeding may occur after activity or exertion, combined with medical history and ultrasonography can help diagnosis, and need to follow the doctor’s advice to take proper rest, and fertility preservation and prevention of infection treatment. 3. Cervical polyps: small amount of vaginal bleeding without abdominal pain may also occur, may recur, ultrasound and gynecological examination can help diagnosis. Repeated bleeding need to follow the doctor’s instructions for polyp tissue removal surgery, and should be sent to the pathology examination. When bleeding occurs in the 14th week of pregnancy, it is necessary to go to the hospital to find out the cause and follow the doctor’s instructions to treat the bleeding actively.