High thyroid hormone in babies may be caused by physiological factors, or it may be caused by hyperthyroidism, the former generally does not require special treatment, the latter needs to be treated with antithyroid drugs such as methylthiouracil under the guidance of a doctor. Some fetuses may have slightly elevated thyroid hormone levels after birth, but generally there are no other abnormalities. It is considered to be caused by increased synthesis of thyroid hormones due to rapid growth and development of the newborn, which is a normal physiological phenomenon and can be observed and followed up periodically, and does not require special treatment for the time being. In addition, elevated levels of thyroid hormones may also be caused by hyperthyroidism, such cases can improve the thyroid function of the complete set of tests, if necessary, can be prescribed by the use of methylthiouracil, methimazole and other antithyroid medication, but children belong to a special group of people should be careful under the guidance of the doctor to use medication. If your baby has a high thyroid hormone level, we recommend that you go to the hospital and ask your doctor to make a judgment and treat your baby under the doctor’s guidance.