Ovarian teratomas include mature teratomas, which are benign tumors. These benign ovarian teratomas do not affect menstruation. However, there are also malignant teratomas, which are immature teratomas. Immature teratomas can secrete hormones, and because they secrete different types of hormones, their impact on menstruation varies. If an ovarian teratoma is diagnosed, immediate surgical treatment is required, because if it is an immature teratoma, it is malignant. Prolonged presence can lead to metastasis. If a teratoma is detected early, early-stage malignant tumors can be cured through surgical treatment.