Newborn heel blood screening for TSH is subject to error. Newborn TSH is primarily designed to screen for congenital hypothyroidism, and if a child is found to have an elevated TSH, this suggests the possibility of congenital hypothyroidism. Under normal circumstances, this method can only screen for primary hypothyroidism and hyper TSHemia, but cannot detect central hypothyroidism, and children with delayed TSH elevation. Therefore, it is important not to assume that a successful screening test means that there is no problem. It is also important to monitor the child’s growth and development, and if the child is found to have delayed expulsion of fetal stools, accompanied by constipation, hypermobility, poor feeding, lethargy, or delayed resolution of jaundice, it is important to have a repeat examination of the thyroid function in order to exclude atypical congenital hypothyroidism.