Congenital hypothyroidism, commonly known as cretinism, is a condition in which the child’s thyroid gland is underdeveloped or has impaired hormone synthesis, resulting in insufficient levels of thyroid hormones in the body, resulting in stunted growth, short stature and mental retardation. This disease can be detected through newborn screening, and early detection and treatment can prevent the occurrence of mental retardation and physical developmental disorders in children. Hypothyroidism is a routine newborn screening test, and blood is routinely collected from the heel of the child 72 hours after birth to detect congenital hypothyroidism in a timely manner, and then treated with effective means to prevent the occurrence of mental retardation.