Prevalence and incidence of precocious pubertal development in Denmark: an epidemiologic study based on national registries.

OBJECTIVE

To our knowledge, no population-based epidemiologic studies on the incidence and prevalence of precocious pubertal development have been published. Danish national registries provide sufficient data for estimating the prevalence and incidence of this condition. The aim of this study was to estimate the prevalence and incidence of precocious pubertal development in Denmark in a 9-year period.

METHODS

The age- and gender-specific incidence rates as well as prevalence rates of precocious pubertal development in Denmark were estimated using data from the Danish National Patient Registry and Statistics Denmark from 1993 to 2001.

RESULTS

Overall, 670 children with precocious pubertal development were registered with a diagnosis of precocious puberty (PP) from 1993 to 2001, corresponding to 50 to 70 new cases of PP per year in Denmark. The incidence of PP was constant during the study period from 1993 to 2001. The incidence of PP subdivided by gender and age at diagnosis was approximately 0.5 per 10000 in girls who were younger than 2 years, decreasing to levels below 0.05 per 10000 in girls aged 2 to 4 years, thereafter gradually rising to 8 per 10000 for girls aged 5 to 9 years. For boys who were younger than 8 years, the incidence was very low (<1 per 10000) and increased only slightly to 1 to 2 per 10000 in boys aged 8 to 10 years. The prevalence of PP was approximately 20 to 23 per 10000 in girls, whereas the prevalence was fivefold lower for boys (<5 per 10000).

CONCLUSIONS

From this first epidemiologic study based on national registries, we estimated that 0.2% of all Danish girls and <0.05% of Danish boys had some form of precocious pubertal development.