Ovarian cysts of 4cm may be physiological cysts, which do not require treatment; if they are pathological cysts, they need to be regularly reviewed and further diagnosed and treated according to the condition of the cysts. 1. Physiological cysts: If women of childbearing age are found to have ovarian cysts of less than 5cm, most of them are physiological cysts, which may be caused by the failure of follicles to be discharged during the ovulation period, and are not accompanied by uncomfortable symptoms. You can review the ultrasound after the end of menstruation, most of the physiological cysts will shrink or disappear, no need to deal with. 2. Pathological cysts: If the cysts are not found to be growing during the examination and there are no uncomfortable symptoms, they are benign tumors and can be left alone for the time being with regular checkups. However, if it is found that the blood flow around the cyst is rich, or the cyst contains solid components, then it is necessary to do further examination of tumor markers. If it is confirmed to be a junctional cyst, or malignant ovarian cyst, surgical removal is required. Therefore, patients with ovarian cysts are advised to consult a doctor in time to complete the relevant examinations and have the doctor confirm the nature of the cysts before making treatment recommendations.