Newborns can be screened for hypothyroidism ten days after birth. Newborns can be screened for hypothyroidism immediately after birth with a heel blood test for thyroid function. In order to avoid the physiologic TSH rise in newborns from influencing the judgment, the heel blood test is performed three days after the birth of the newborn. Therefore, newborns can also be screened for hypothyroidism ten days after birth. Some newborns may have temporary hypothyroidism because the thyroid function is not yet fully developed, and abnormal thyroid hormone levels can be seen in the early checkups, which will usually return to normal in about three months, and it is recommended to monitor the thyroid hormone levels on a regular basis. However, if the hypothyroidism is primary, drug treatment should be considered in time to avoid affecting the growth and development of the child. If hypothyroidism is suspected in newborns, immediate medical attention should be sought and active treatment should be provided.