Soy allergy following early soy feeding in neonates

Background: Feeding neonates with humanized milk formula in maternity hospitals may increase the prevalence of milk allergy in infants. However, prospective studies of the possible allergenic effect of very early soy-based formula feeding are lacking. Objectives: To assess the prevalence of soy allergy in infants fed soy-based formula in the first 3 days of life. Methods: The study group included 982 healthy fullterm infants born within a 7 month period at a hospital that routinely uses soy-based formula to supplement breastfeeding. In-hospital feeding was recorded and the parents were interviewed once monthly over the next 6 months regarding feeding practices and clinical symptoms suggesting soy allergy in the infant. Results: Ninety-nine percent of the infants received soybased formula supplement in hospital, and 33%-42% at home. No cases of immediate allergic reaction to soy or soyinduced enterocolitis were reported. Conclusions: The use of soy-based formula in the early neonatal period does not apparently increase the prevalence of soy allergy in infants followed for the next 6 months.