Prevalence of permanent primary congenital hypothyroidism in Taiwan.

The purpose of this study was to find the prevalence of permanent primary congenital hypothyroidism in Taiwan. From January 1988 to December 1990, there were 991,132 live births in Taiwan. Of these, 329,891 neonates were screened for primary congenital hypothyroidism. Fifty-seven cases of permanent primary congenital hypothyroidism were confirmed. Hence, the prevalence of permanent primary congenital hypothyroidism in that period in Taiwan was 1 in every 5,788 live births. There was a female preponderance with a female to male ratio of 1.7. Of 54 infants who had a thyroid scan, 36 were found to have an ectopic thyroid gland, while 11 were found to have dyshormonogenesis. Among the 57 infants, one case with a delayed rise in the serum thyrotropin level was missed on initial screening. When compared with other studies, these data suggest that the prevalence of permanent primary congenital hypothyroidism varies in different ethnic groups throughout the world.