Congenital hypothyroidism (CH), occurring in approximately 1:2000 to 1:4000 newborns [1], is one of the most common preventable causes of intellectual disability [2]. Screening programs for CH have been developed in many countries [3]. There are three screening methods used including primary thyroid-stimulating hormone (TSH) with backup thyroxin (T4), primary T4 with backup TSH, and combined TSH plus T4 method. Primary TSH with backup T4 is more sensitive while primary T4 with backup TSH is more specific in detecting CH [4].

This retrospective study was done to assess the prevalence of congenital hypothyroidism among children born in Arar Central Hospital, Arar city, Kingdom of Saudi Arabia between 2008 and 2014. We analyzed records from 19,013 deliveries and 18,989 screened newborns. Blood samples were collected on filter paper from newborns on the fifth day after delivery, and tested for both TSH and T4. The cut-off value for TSH was 10 mU/L.

The prevalence of hypothyroidism among newborns for the whole observation period 2008 to 2014 was 3.1 per 10,000 in males and 2.1 per 10,000 in females, and the total prevalence was 2.6 per 10,000 (0.03%) (Table I).

TABLE I	Details of Newborns Screened for Hypothyroidism

The incidence of congenital hypothyroidism in our area is similar to that reported in other countries [5], but lower than that reported in Najran, a southern province of Saudi Arabia, where the incidence has been reported to be 1 in 1400 [6]. Other studies in the country reported an incidence of 1 in 2500 to 1 in 3500.

In conclusion, the prevalence of congenital hypothyroidism in Arar City, Saudi Arabia for the observation period between 2008 to 2014 was 2.6 per 10,000 (0.03%) with no gender differences.

Contributions: All authors were involved in conceptualizing the study and acquisition/analysis of data. SAA, SHA and AAB drafted the manuscript, which was critically revised by HTM and AMA.

Funding: Deanship of scientific research, Northern Borders University, Arar city, Kingdom of Saudi Arabia. Competing interest: None stated.

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4. American Academy of Pediatrics,　 Rose SR;　American Thyroid Association,　 Brown RS; Public Health Committee, 　Lawson Wilkins Foley T, Keplowitz PB, Kaye CI, et al. Pediatric Endocrine Society. Update of newborn screening and therapy for congenital hypothyroidism. Pediatrics. 2006;117: 2290-303.

5. Al-Jurayyan NA,　Shaheen FI,　Al-Nuaim AA,　Al-Desouki MI,　Faiz A,　Al Herbish AS,　et al. Congenital hypothyroidism: Increased incidence in Najran Province, Saudi Arabia. J Trop Paediatr. 1996;42:348-51.