The aim of this study was to understand the natural course of egg allergy and to identify the prognostic factors for tolerance. A retrospective study that included 106 children with atopic dermatitis and egg allergy diagnosed at less than 2 years of age was conducted using medical records and parental telephone interviews. Tolerance was defined as the absence of an allergic reaction in response to the parental introduction of cooked eggs to the diet of children whose egg white specific IgE level had decreased to less than 1.5 kU(A)/l. The median age of tolerance to egg allergy was 4 years. Kaplan-Meier analysis predicted that 41% of children had developed tolerance to egg allergy by age 3, while 60% of children had developed tolerance by age 5. The age at the diagnosis of egg allergy was the only significant prognostic factor of egg allergy tolerance identified by the Cox proportional regression model.