Ovarian cysts are fluid-filled sacs formed in the ovary. Most often, they go away on their own with no harm. In reproductive years, in each cycle women release an egg from a fluid-filled sac (follicle). However, the size of this sac (follicle) usually is smaller than 3 cm. If the size becomes larger than 3 cm, it is called cyst. An ovarian cyst may or may not produce symptoms. Some of the most common symptoms of an ovarian cyst include abdominal or pelvic pain, changes in the periods, bloating, pain during sex, or pain with menstruation. Larger cysts may cause torsion (twisting of the ovary) which is typically very painful. Simple cysts are very likely benign, but solid components into the cyst could be a sign of more serious ovarian tumors or ovarian cancers. Diagnosis of ovarian cysts usually is made by pelvic exam or pelvic ultrasound. Several treatment options are available. Choosing an option depends on many factors, including the type of cyst, whether you have symptoms, your family history, how large the cyst is, and your age. Treatment options include watchful waiting, birth control pills, and surgery. Your doctor will help you take the appropriate action to make sure that the cyst does not grow or cause problems.