Supplementary feeding in maternity hospitals and the risk of cow's milk allergy: A prospective study of 6209 infants

Background: Early; feeding with cow's milk (CM) may increase the risk of co w's milk allergy (CMA). Objective: We sought to examine prospectively whether supplementary feeding of CM at the maternity hospital would increase the risk when compared with feeding with pasteurized human milk or hydrolyzed formula, Methods: We studied 6209 unselected healthy, full-term infants, of whom 538 5 (87%) required supplementary milk while in the hospital. The infants were randomly assigned to receive CM formula (1789 infants), pasteurized human milk (1859 infants), or whey hydrolysate formula (1737 infants). The comparison group (824 infants) was composed of infants who were exclusi vely breast-fed. The infants were followed for 18 to 34 months for symptoms suggestive of CMA. The primary endpoint was a challenge-proven adverse rea ction to CM after a successful CM elimination diet. Results: The cumulative incidence of CMA in the infants fed CM was 2.4% Com pared with 1.7% in the pasteurized human milli group (odds ratio [OR], 0.70 ; 95% confidence interval [CI], 0.44-1.12) and 1.5% in the whey hydrolysate group (OR, 0.61; 95% CI, 0.38-1.00), In the comparison group, CMA develope d in 2.1% of the infants. Among the infants who required supplementary feed ing at hospital, both exposure to CM while in the hospital (OR, 1.54; 95% C I, 1.04-2.30; P = .03) and obvious parental atopy (OR, 2.32; 95% CI, 1.53-3 .52; P < .001) increased the risk of CMA, zConclusions: Our data indicate that feeding of CM at maternity hospitals i ncreases the risk of CMA when compared with feeding of other supplements, b ut exclusive breast-feeding does not eliminate the risk.