Prevalence of Congenital Hypothyroidism in Mazandaran Province, Iran, 2008

Background and Âlthough congenital hypothyroidism is a preventable cause of mental disabilities, less than 10% of newborns are diagnosed based on clinical symptoms in the first month. Ând if the diagnosis is not made based on screening programs, it would be delayed and irreparable cerebral and auditory complications will result. The purpose of this study was to determine the prevalence of congenital hypothyroidism in the Mazandaran province. The study is a descriptive (screening) survey. From infants born from January 2007 to January 2008 in Mazandaran province heel blood samples on filter paper were obtained. TSH values were measured by ËLÏSÂ method and TSH> 5 mlu/L was considered as the recall criterion. Diagnosis of neonatal hypothyroidism was made based on TSH>10 and T4<6.5. Treatment was performed based on the results of second tests. Ëxcept in cases where the initial TSH was greater or equal to 20 -where the treatment was started from the beginning- if the second test results were reported normal, treatment was discontinued and the case was considered as a transient hypothyroidism. Ôut of 45218 infants studied, 49% were female and 51% were male. 4.6% of newborns (2109) were recalled, among whom 1885 had 5< TSH< 10 mlu/L and 185 had 10< TSH< 20 mlu/L and 39 had TSH ³ 20.73 infants were diagnosed with hypothyroidism. Thus, the prevalence of neonatal hypothyroidism was 1.6/1000 in live births in Mazandaran province. Âlso prevalence of transient neonatal hypothyroidism was 1 in every 2500 live births.Çonclusion: Given the high prevalence of hypothyroidism in the province, more screening program is essential.