A prospective study of infantile hemangiomas with a focus on incidence and risk factors.

Infantile hemangiomas (IHs) are the most common tumor of infancy and have been estimated to occur in 4% of infants. Only two previous incidence studies of IH in a healthy population have been published, and both of these were performed in the first week of life. The objective was to identify the incidence of IH in an Australian neonatal population and characterize the risk factors. All women who presented to the postnatal ward in a 200-bed maternity hospital were asked to complete a questionnaire. Details of maternal history and birth details were recorded. Two follow-up emails 3 and 6 weeks after discharge were sent to all mothers who consented, asking if their baby had developed an IH. Babies reported to have an IH were seen in clinic to confirm the diagnosis. Details were collected from 1,034 mothers of 1,065 babies; 28 (2.6%) of the infants developed IH. Babies that developed IH were more likely to be female (p < 0.001), have a low birth weight (p = 0.020), be born at a gestational age of <37 weeks (p = 0.005), and be conceived through in vitro fertilization (IVF) (p = 0.001) than those who did not. The incidence of IH at 6 weeks of life was 2.6%.