Deladoëy J, Bélanger N, Van Vliet G. Random Variability in Congenital Hypothyroidism from Thyroid Dysgenesis over 16 years in Quebec. J Clin Endocrinol Metab 2007; 92: 3158-3161.

    • Cited in the Yearbook of Pediatric Endocrinology 2008 (Karger).

Only random variability was observed in the monthly and yearly incidences of congenital hypothyroidism from thyroid dysgenesis (CHTD) over 16 consecutive years in the Province of Quebec. We reported the largest number of CHTD cases ascertained by thyroid scintigraphy and the time period analyzed herein is the longest observation documented so far. Therefore, our results strongly argue against a significant environmental influence on thyroid gland differentiation and migration during embryogenesis.