title: Urine and milk iodine concentrations in healthy and congenitally hypothyroid neonates and their mothers.
abstract: BACKGROUND
  In view of the high prevalence of Congenital Hypothyroidism (CH) in Iran, in this study we evaluated the role of iodine in the aetiology of CH by comparing urine and milk iodine concentrations in healthy and congenitally hypothyroid neonates and their mothers.
  
  
  METHODS
  In a cross-sectional study, urinary iodine concentrations (UIC) in newborns with CH, as well as UIC and the milk iodine concentrations (MIC) of their mothers, were measured and compared with a control group. The lower, mid, and upper range of UIC for neonates and lactating mothers was considered to be < 150 μg/L, 150-230 μg/L, and > 230 μg/L, and lower, mid, and upper range of MIC was considered to be < 150 μg/L, 150-180 μg/L, and > 180 μg/L, respectively.
  
  
  RESULTS
  The median UICs in subjects with CH (n = 68) and healthy subjects (n = 179) were 300.5 and 290.5 μg/L, respectively (P > 0.05). The median UICs in the case and control groups were 150 and 130 μg/L, respectively (P > 0.05). The median MIC in the case group was higher than in the control group (210 μg/L v. 170 μg/L, P < 0.05).There was a positive correlation between newborn UIC and MIC. There was no significant correlation between newborn UIC and serum TSH, maternal UIC and maternal MIC, or newborn UIC and serum TSH.
  
  
  CONCLUSIONS
  There is no inadequacy in iodine intake in the studied population. Iodine excess could be a possible risk factor for CH, but there were findings, such as lack of correlation between maternal MIC and UIC, and the median neonatal UIC, which was similar in the two groups, so, drawing conclusions should be done with some caution and requires further studies.
authors.affiliation: Endocrine and Metabolism Research Centre, Isfahan University of Medical Sciences, Isfahan, Iran.
authors.forename: Mahin
authors.initials: M
authors.lastname: Hashemipour
authors.forename: Peyman
authors.initials: P
authors.lastname: Nasri
authors.forename: Silva
authors.initials: S
authors.lastname: Hovsepian
authors.forename: Rezvane
authors.initials: R
authors.lastname: Hadian
authors.forename: Kamal
authors.initials: K
authors.lastname: Heidari
authors.forename: Hossein Movahedian
authors.initials: HM
authors.lastname: Attar
authors.forename: Massoud
authors.initials: M
authors.lastname: Amini
authors.forename: Leili
authors.initials: L
authors.lastname: Moohebat
authors.forename: Ali
authors.initials: A
authors.lastname: Sajadi
authors.forename: Ali
authors.initials: A
authors.lastname: Ajami
mesh_terms: D000328:Adult; D003409:Congenital Hypothyroidism / Q000453:epidemiology / Q000652:urine*; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007455:Iodine / Q000032:analysis* / Q000652:urine; D007492:Iran / Q000453:epidemiology; D008895:Milk, Human / Q000737:chemistry*; D009035:Mothers; D012016:Reference Values
chemical_list: D007455:Iodine