Pregnancy-related hyperthyroidism is common and usually occurs in early pregnancy and is closely related to elevated chorionic gonadotropin levels. When a woman enters the second trimester, i.e., after 4-7 months of pregnancy, her chorionic gonadotropin level stabilizes, her thyroid function gradually becomes normal and her hyperthyroidism gradually disappears. After pregnancy, human chorionic gonadotropin levels increase significantly, and with the rapid hormonal changes, hyperthyroidism may occur. Generally, mild hyperthyroidism does not require treatment, and the body will not have obvious symptoms, but only regular review to detect the condition. After mid-pregnancy, human chorionic gonadotropin levels will not continue to rise and the symptoms of hyperthyroidism will gradually disappear. However, if the condition is severe and does not disappear after mid-pregnancy, the patient should take medication to regulate thyroid function under the guidance of a doctor. If left untreated, it may lead to miscarriage or fetal developmental malformations.