Blockage of menstrual flow with stomach pain during menstruation may be related to cervical or cervical canal adhesion, inflammation, ectopic pregnancy and other reasons. 1. Cervical adhesion: If you have undergone multiple uterine surgeries or have bacterial infection at the cervix, it may lead to adhesion of the cervix, which may lead to decreased menstrual flow and stomach pain. 2. Inflammation: If there are symptoms of vaginitis or pelvic inflammatory disease, it may lead to hidden pain in the lower abdomen and changes in menstrual flow; as the condition worsens, fever and chills may also occur. 3. Ectopic pregnancy: If women who have recently had sexual intercourse but their menstrual period has not come on time, if there is ectopic pregnancy miscarriage and other conditions, there may be hidden pain in the lower abdomen and other symptoms. There are many reasons for women to have clogged menstrual blood with stomach pain during menstruation. If the above symptoms occur, it is recommended to consult a doctor in time and handle the case accordingly.