Endometriosis is a common condition in which small pieces of the uterus (womb) lining, known as the endometrium, are found outside the uterus. This could be in the fallopian tubes, ovaries, bladder, bowel, vagina, rectum and other places. Endometriosis may not produce any symptoms, or it may commonly cause painful menstruation, and pain in the lower abdomen, pelvis or lower back. It may also lead to infertility. Those between age 25 and 40 are most affected. It is a long-term condition with no known cure, but symptoms can be managed and fertility improved with pain medication, hormone treatment or surgery, so that the condition does not interfere with daily life.