Endometriosis is a condition where the uterine lining implants itself in other areas of the pelvis, causing cysts and adhesions. It commonly affects women of reproductive age and causes painful periods, painful intercourse, and infertility. While the causes are unknown, potential factors include genetics, retrograde menstruation, immune problems, and estrogen levels. Diagnosis is usually via laparoscopy surgery. Treatment options include surgical removal of growths, hormonal therapy to suppress menstruation, and pain medication. Endometriosis has no cure but combination therapies can help manage symptoms and fertility issues.