Endometriosis is a sickness when tissue similar to, but not identical to, endometrium cells of the uterus grow outside the uterus. As many as 11% of American women between 15 and 44 years-old may have this sickness. It is most commonly diagnosed in women 30-40 years-old, but affects people of every age and gender. Having endometriosis can sometimes affect fertility. Endometriosis symptoms can be treated by a doctor, but cannot be cured. Wide-excision surgery can reduce or stol recurrence of disease. Treating endometriosis may help a woman get pregnant.