Endometriosis refers to a common gynecological disease in women that is formed by the active endometrial cells implanted outside the endometrium. The endometrial cells should be grown in the uterine cavity, but because the uterine cavity communicates with the pelvic cavity through the fallopian tubes, the endometrial cells can enter the pelvic ectopic growth via the fallopian tubes. The lesion can affect all pelvic tissues and organs, and is most common in the ovary, uterus rectum, and uterine ligament, and can also occur in the abdominal cavity, chest, limbs, and so on. Even you have hysterectomy, it can still grow in other places.