Journal of School of Public Health and

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Background and Aim: The prevalence of congenital hypothyroidism (CH), one of the main causes of preventable mental handicap in neonates, is much higher in Iran than the global average.
The objective of this study was to identify risk factors for congenital hypothyroidism (CH) by using the screening program in Fars Province, Iran, during the period 2003-2006.

Methods and Materials: A case-control study was carried out, the samples being 126 cases and 401 controls. The neonates were those born between 2003 and 2006, under coverage of the National Congenital Hypothyroidism Program. The data were analyzed using the univariate and multivariate analysis tests.

Results: An increased risk for CH was detected in infants with consanguine parents, by a multivariate analysis test (odds ratio (OR) = 2.9, 95% confidence interval (CI):1.8-4.8). The test also confirmed previously reported statistically significant associations with additional birth defects OR = 2.2 (1-4.6), birth defects in first-degree relatives OR = 4.7 (1.6-4.8), female gender OR = 1.9 (1.1-3), and twin births. Although not significant, an increased risk for CH was observed among infants with gestational age<30 weeks (preterm delivery) (OR = 1.7(0.9-1.3)).

Conclusion: This study identified risk factors contributing to the etiology of CH. In particular, our results suggest a multifactorial origin of CH, in which both genetic and environmental factors play a role.

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Background and Aim: Congenital hypothyroidism is the most common metabolic disease and endocrine disorder in children and a major cause of mental retardation, which can be prevented only through early diagnosis and treatment. This study aimed to determine the prevalence of congenital hypothyroidism in newborns referred to Shahid-Ghodsi Health Center in Mashhad, Iran.
Materials and Methods: This cross-sectional study, including 4484 newborns referred to Shahid-Ghodsi Health Center for congenital hypothyroidism screening, was conducted during the first six months of 2015. Data were collected from the screening forms and analyzed using the statistical software SPSS 21, the tests being the two-sample T-test, analysis of variance, Chi-square and Fisher's exact tests; in all the tests the significance level was 5%.
Results: Of the 4484 neonates screened, 51% and 48% were males and females, respectively. The recall rate was estimated to be 2.6% and prevalence of the disease 1 in 370 neonates. There were statistically significant associations between hypothyroidism on the one hand and birthweight, type of feeding (nutrition), primary and serum TSH levels of the neonate on the other.
Conclusion: Based on the findings, the prevalence of congenital hypothyroidism in Mashhad is significantly higher than that national and global averages. It is essential to conduct more comprehensive research to determine the associated factors and design suitable interventions in order to prevent the disease.