Many people are nervous when they find an ovarian cyst after an ultrasound, and some doctors even recommend surgery, when in fact most do not require treatment. Non-redundant ovarian cysts are cysts caused by fluid retention in the follicles or corpus luteum of the ovary, also known clinically as retention cysts. They are usually smaller than 5 cm. The disease can be divided into follicular cysts, corpus luteum cysts, follicular membrane flavin cysts, and chocolate cysts. The first three types of cysts are also called functional (physiologic) ovarian cysts. Follicular cysts and follicular lutein cysts have no clinical symptoms; luteal cysts often have persistent or irregular vaginal bleeding and prolonged menstrual cycles; and chocolate cysts are pathologic. All four cysts occur mostly in the reproductive years. 1. Follicular cysts occur most often due to the non-rupture of mature follicles or the continued growth of atretic follicles, resulting in fluid retention in the follicular cavity. 2. Luteal cysts are due to the persistence or growth of the cystic corpus luteum, or luteal hematoma containing more blood, which increases fluid retention after the blood is absorbed. 3, Follicular membrane flavin cysts are formed due to increased levels of chorionic gonadotropin or increased sensitivity of follicles to chorionic gonadotropin causing follicular membrane cells to become flavinized. 4. Chocolate cysts are “endometriotic” cysts that occur in the pelvis and are benign, infiltrative, hormone-dependent diseases. Under normal circumstances, the endometrium grows in the uterine cavity and is influenced by female hormones in the body, shedding once a month to form menstruation. If the endometrial fragments shed during menstruation enter the pelvic cavity via the fallopian tubes with the menstrual blood, they can be planted on the surface of the ovaries or other parts of the pelvis, forming ectopic cysts. This ectopic endometrium is also influenced by sex hormones and repeatedly sheds and bleeds with the menstrual cycle. If the lesion occurs on the ovary, there is localized bleeding during each menstrual period, causing the ovary to enlarge and form a cyst containing old blood, which is brown in color and thick like paste, resembling chocolate, hence the name “chocolate cyst”. These cysts can gradually increase in size, sometimes rupture during or after menstruation, and occasionally become malignant. The treatment for the four types of cysts mentioned above is different. Follicular cysts and corpus luteum cysts are mostly self-absorbing, do not affect ovulation, and do not affect health, and are not treated. Follicular membrane luteinizing cysts may persist for a long time, but usually subside naturally after delivery or healing of trophoblastic lesions. Therefore, no treatment is also needed, and surgery is only feasible in case of rupture and bleeding or tip torsion. In contrast, chocolate cysts, because of the possibility of malignancy, should be promptly seen by a doctor for laparoscopic surgery to remove them. After surgery, medication should be continued to avoid recurrence. Differentiation method: The first three types of cysts may gradually shrink in different menstrual cycles , and chocolate cysts are often accompanied by an increase in ca-125 during the tumor series examination of the main.