Increasing incidence of infantile hemangiomas (IH) over the past 35 years: Correlation with decreasing gestational age at birth and birth weight.

Background: Infantile hemangiomas (IH) are the most common soft-tissue tumors of infancy, but little is known regarding their true incidence.

Objectives: We sought to determine the current incidence of IH and examine trends in incidence, demographics, and lesion characteristics over 3 decades.

Methods: The Rochester Epidemiology Project was used to identify infants residing in Olmsted County, Minnesota, who were given a diagnosis of IH between January 1, 1976, and December 31, 2010.

Results: In all, 999 infants were given a diagnosis of IH. Incidence increased over the 3-decade study period from 0.97 to 1.97 per 100 person-years (P < .001). Average gestational age at birth and birth weight for infants with IH decreased over the study period (39.2-38.3 weeks, P < .001 and 3383-3185 g, P = .003, respectively). The overall age- and sex-adjusted incidence of IH was 1.64 per 100 person-years (95% confidence interval 1.54-1.75).

Limitations: The population of Olmsted County, Minnesota, is predominantly non-Hispanic white, limiting our ability to report racial differences in incidence. This was a retrospective study.

Conclusions: This study provides a longitudinal, population-based incidence of IH. Incidence has increased steadily over the past 3 decades, correlating significantly with decreasing gestational age at birth and birth weight in affected infants.