Anal cramps with menstruation can be caused by pelvic congestion or by endometriosis. During menstruation, due to pelvic congestion there will be abdominal cramps, lumbar pain, back pain or mild anal cramps. There is no need to treat this condition, which will gradually ease with rest and warmth. If you have endometriosis, you may usually have more severe menstrual cramps and more severe anal cramping when you have your period. If you always feel like having a bowel movement, you can go to the hospital to have an ultrasound or have blood drawn to check CA125.If you are sure that it is caused by endometriosis, you can take short-acting contraceptive pills to regulate it. During menstruation, pay attention to rest, can not be cold, can not be tired, otherwise it will make the symptoms of anal distension aggravated, pay attention to hygiene during menstruation, can not have sex.