Bleeding again after 12 days of menstruation may be caused by irregular vaginal bleeding due to miscarriage with precursor, menstrual disorders or cervical diseases. 1. Pre-eclampsia: If a woman has recently had sexual intercourse and has bleeding 12 days after her period has ended, it may be a sign of pre-eclampsia. 2. Menstrual disorders: bleeding after 12 days of menstruation may be caused by menstrual disorders. 3. Cervical diseases: If a woman has bleeding again 12 days after the end of menstruation, she needs to consider cervical diseases such as cervicitis or cervical cancer if the bleeding is during coitus or transvaginal examination. This is because these diseases can cause vaginal contact bleeding. Bleeding 12 days after the end of menstruation, there may be other reasons, it is recommended to go to the hospital in time to improve the examination to clarify the cause of the disease, under the guidance of the doctor to give targeted treatment.