Normally, every month, your uterus breaks down tissue, shedding its lining and creating cramping in the process. In endometriosis, some of your uterine tissue or “period lining” ends up where it shouldn’t, including the lining of your abdomen. Oddly enough, when that tissue travels outside your uterus, it still acts like it’s part of your period, so it still swells and cramps without your body being able to release it, creating awful pain.
Periods should become less painful as you age, not worse. So if you notice your periods getting worse, pay attention and schedule an appointment with your doctor.