Background: Types of Congenital hypothyroidism are classified into permanent and transient (CH). Permanent (CH) refers to a persistent deficiency of thyroid hormone that requires life-long treatment. Transient CH refers to a temporary deficiency of thyroid hormone, discovered at birth, but then recovering to normal thyroid hormone production. Recovery occurs in the first few months or years of life. Permanent (CH) can be further classified into permanent primary and secondary (CH) transient primary (CH) has also been reported associated with defects in other organ systems. The underlying etiology of(CH) typically will determine whether hypothyroidism is permanent or transient