Ovarian teratomas should try not to exceed 5 centimeters. Ovarian teratoma is a common germ cell tumor in women. Although most ovarian teratomas are benign tumors, a very small percentage of ovarian teratomas are immature teratomas with the possibility of malignancy. The degree of malignancy of ovarian teratoma cannot be determined without surgical treatment and pathological examination. If the ovarian teratoma is less than 5 centimeters and the patient has no obvious symptoms, the risk of malignant transformation is small, so it can be observed for a short period of time, but it should be closely followed up under the guidance of the doctor. However, if the ovarian teratoma is more than 5 cm, it is an indication for surgery, because larger ovarian teratomas are likely to cause local compression symptoms, and may cause ovarian cyst tip torsion leading to ovarian necrosis, and the risk of malignant changes increases. Therefore, if the ovarian teratoma does not exceed 5 centimeters, it can be temporarily observed and closely followed up, but if it is larger than 5 centimeters, it should be treated with surgery as soon as possible.