Endometriosis (when characterized by endometriomas, also known as chocolate cysts) is a condition where endometrial tissue, which normally lines the inside of the uterus, grows outside the uterus, in areas such as the ovaries, fallopian tubes, and pelvic tissues within the pelvic region. It can also affect nearby organs like the bowel and bladder, and rarely, may appear in other parts of the body. Estimated to affect approximately 5-10% of women of reproductive age, endometriosis is considered one of the significant causes of infertility.

While pain relievers and hormonal therapies can be used to alleviate the symptoms of endometriosis, surgical intervention may be necessary to address fertility issues or remove widespread lesions.