what cause cyst on ovaries
Conditions that cause ovarian cysts. In some cases, ovarian cysts are caused by certain conditions, such as endometriosis. Endometriosis occurs when pieces of the tissue that line the womb (endometrium) are found outside the womb in the fallopian tubes, ovaries, bladder, bowel, vagina or rectum. Blood-filled cysts can sometimes form in this tissue.