Corpus luteum cyst occurs due to:

Grandiose lutein cyst Functional, non neoplastic.enlargement of the ovary.:, Persistent corpus luteum cyst may cause local pain, tenderness or delayed menstruation Cysts are often palpable clinically Usually resolve spontaneously ​Theca lutein cyst They are associated tropphoblastic disease, chorionic gonadotrophin therapy (HCG) & clomiphene therapy. They are bilateral and filled with straw coloured fluid. They resolve spontaneously after elimination of the H mole, therapeutic curettage, destruction of chorio-carcinoma or discontinuation of gonadotrophin therapy.