Introduction Endometriosis is one of the most common reproductive diseases affecting women of reproductive age. The most common symptoms of endometriosis are pelvic pain and infertility. Less commonly, endometriosis results in cyclic bleeding or pain in a wide variety of locations. An undetermined proportion of patients with endometriosis remain asymptomatic. Depending on a woman's symptoms and fertility desires, treatment options can range from medical management to conservative surgery or definitive surgery, including hysterectomy and bilateral salpingo-oophorectomy. Definition Endometriosis is defined as the presence and growth of functioning endometrial glands and stroma in places other than the uterine cavity. Although endometrial implants are microscopically similar to eutopic endometrium, careful physiological and molecular studies have demonstrated that endometriosis implants differ in several important ways from normal endometrium. These hormonally responsive implants are most commonly found in the pelvis but have been reported to occur in almost every imaginable area of the body. Epidemiology Endometriosis is a relatively common disease with a prevalence of approximately 10% among women of reproductive age in the USA. Because of the association of endometriosis with pelvic pain and infertility, this diagnosis has become the third leading cause of gynecological hospitalizations in the USA and is among the most common indications for hysterectomy.