Thyroid function is very important in babies, because thyroid hormones play a role in regulating the growth and proper development of the baby's body. Newborn thyroid test is a simple and feasible method that is used for early diagnosis of thyroid disorders in babies. This test measures the level of thyroid hormones in the baby's blood and shows whether the baby's thyroid activity is within the normal range or not. In the rest of this article, we will provide more comprehensive information on this topic from Dr. Ali Faraji's website. Proper thyroid function in babies In the first step, note that you must; If you see any suspicious and worrying symptoms in your baby, go to the doctor as soon as possible so that the doctor can start the diagnosis and treatment process and ensure the health of your baby. Things that are necessary for the proper functioning of the thyroid include the following: 1) Thyroid hormone production The infant's thyroid is responsible for the production of thyroid hormones, especially thyroxine (T4). These hormones play a role in regulating the rate of metabolism, cell growth and general development of the baby. 2) production of resting thyroid hormone (TSH) TSH is produced by the pituitary gland and signals the thyroid to secrete thyroid hormones. If the production of thyroid hormone decreases, the TSH level will rise so that the thyroid produces more thyroid hormones. 3) Thyroid tests Blood tests are usually used to evaluate thyroid function in infants. These tests include measuring the levels of thyroid hormones (T4 and T3) and TSH. The results of the tests help the doctor to evaluate the condition of the baby's thyroid function. The importance of a healthy thyroid on the growth of the baby In general, a healthy thyroid is very important in babies, and defects in its function can lead to serious problems in the growth and development of the baby. Thyroid hormones, which are secreted by the thyroid, play a vital role in regulating the growth and development of the baby. Below, I will explain the importance of a healthy thyroid on the development of the baby: - Physical growth - Neurological, verbal and behavioral development - Regulation of metabolism and energy supply of the baby Signs and symptoms of thyroid disorder in babies Thyroid disorders in babies can occur in two forms: hypothyroidism or hypothyroidism and hyperthyroidism or hyperthyroidism. In the following, I will explain to you the signs and symptoms of these disorders in babies: - Insufficient growth: A baby with hypothyroidism may have insufficient growth and weigh less than normal. - Delay in growth and development: This disorder can lead to a delay in the physical growth and intellectual and physical development of the baby. - Lameness in hair growth: The hair of a baby with hypothyroidism is usually thin and less textured, and it may be observed that it is not growing. - Dry skin: the baby's skin becomes dry and itchy and may also show problems such as cracks and yellow skin. - Abnormal growth: A baby with hyperthyroidism may grow excessively and weigh more than normal. - Quiet behavior: the baby may be very quiet and nervous and does not show signs of relaxation. - Acceleration of heart rate: The heart rate of a baby with hyperthyroidism is usually much faster than normal. - Trembling of hands and feet: Trembling of hands and feet is one of the signs of hyperthyroidism in babies. Methods of diagnosing thyroid disorders in infants Diagnosing thyroid disorders in infants is usually done through infant thyroid testing and clinical evaluation. Below, I will explain to you the methods of diagnosing thyroid disorders in babies: ### 1- Papil tape test: This test is used to measure the level of thyroid hormone (TSH) in the blood. In case of thyroid disorders, TSH level is usually increased or decreased. ### 2- Measurement of thyroid hormones: The level of thyroid hormones such as T3 (triiodothyronine) and T4 (thyroxine) in the blood is checked. In hypothyroidism, T3 and T4 levels are decreased, while in hyperthyroidism, these levels are increased. ### 3- Examination of clinical history and symptoms: The doctor makes a careful examination of suspected signs and symptoms related to thyroid disorder in infants. This includes checking the baby's growth and development, skin condition, behavior, feeding, and other thyroid-related symptoms. ### 4- Thyroid ultrasound: Thyroid ultrasound can help evaluate the size and shape of the thyroid gland and detect structural defects. This method is usually used in cases of suspected hereditary hypothyroidism or structural factors. ### 5- Additional tests: In some cases, additional tests are also performed to make a more accurate diagnosis and investigate major causes. This includes molecular tests for genetic testing, skin tests for thyroid hormone sensitivity, and imaging tests such as tomography and MRI. Treatment and prevention of thyroid disorders in infants Treatment and prevention of thyroid disorders in infants depends on the type of thyroid disorder and its cause.