Types of Ovarian Cysts Functional Cysts: Formed during the menstrual cycle, these cysts include follicular cysts (from the follicle that doesn't release an egg) or corpus luteum cysts (when the follicle reseals after releasing the egg). Pathological or Non-functional Cysts: Arising from abnormal cell growth, these cysts might include endometriomas or cystadenomas. Polycystic Ovaries (PCOS): Characterized by multiple small cysts on the ovaries due to hormonal imbalances, often accompanied by irregular periods and other symptoms. Hemorrhagic Cysts: These result from bleeding into a cyst and may cause sudden, severe pelvic pain.