F Amiri , H Sharifi, E Ghorbani , Fs Mirrashidi, M Mirzaee, N Nasiri,
Volume 15, Issue 2 (Vol.15, No.2 2019)
Abstract
Background and Objectives: Congenital hypothyroidism is one of the reasons for mental retardation and premature death of infants. Since identification of the determinants of hypothyroidism plays a significant role in its prevention, this study was conducted to determine the prevalence of congenital hypothyroidism and to investigate its determinants in newborn infants.
Methods: This study was a secondary analysis of the data of the neonatal congenital hypothyroidism screening program. Hypothyroidism was diagnosed based on the Thyroid Stimulating Hormone (TSH) level in the heel prick blood samples on the third to fifth day of life. The data of infants born in Jiroft hospitals were collected from Jiroft Health Center and analyzed using descriptive statistics and Poisson regression test.
Results: In this study, 4998 newborns (2450, 49.02% female, 2548, 98 / 50% male) were investigated. The study samples were newborns born from March to March 2016. The prevalence of congenital hypothyroidism was 1 in 135 live births. The prevalence of congenital hypothyroidism was higher in babies born by cesarean section (IRR = 2.2, 95% CI =1.1-4.1), newborns admitted to the NICU (IRR = 4.6, 95% CI=2.4-8.9), and babies with high birth weight (IRR = 5.3, 95% CI =3.5-8.1).
Conclusion: The prevalence of hypothyroidism was higher in this study compared to other studies. Its prevalence was higher in males than in females. Genetic and environmental differences may explain this difference. The prevalence of hypothyroidism was higher in infants born through cesarean section and newborns hospitalized in NICU.