Ovarian cysts are fluid-filled sacs that develop on the ovaries, which are part of the female reproductive system. They are common and often occur during the menstrual cycle. Most ovarian cysts are benign, meaning they are not cancerous, and many women may not even realize they have them since they often cause no symptoms. In some cases, ovarian cysts can lead to discomfort or complications, such as pain or pressure in the abdomen. Regular check-ups with a healthcare provider can help monitor any cysts and ensure they do not pose a health risk. Treatment may be necessary if a cyst becomes large or causes significant symptoms.