The 209 mothers to be, enrolled in a randomized, prospective, allergy-prevention study from allergy-prone families, totally abstained from cow's milk and egg from gestational week 28 to delivery. This article presents the development of allergic disease at 5 years of age in their children, compared with the development of allergic disease in the children of the control mothers who took normal food throughout pregnancy. The prevalence of allergic disease could be evaluated in 198 children (95%). Allergic disease was monitored with questionnaires, skin prick testing, serum-IgE determinations, and physical examination. Eczema, allergic rhinoconjunctivitis, and asthma was equally common in the groups. Persistent food intolerance to egg was significantly more common in children of the mothers receiving the diet. This long-term follow-up confirms our previous findings that maternal elimination diet during late pregnancy does not prevent the development of allergic disease in the genetically predisposed child.