Effect of maternal egg consumption on breast milk ovalbumin concentration

Summary Background Maternal dietary avoidance of egg has been recommended to treat egg allergy in breastfed infants. However, only one of three randomized controlled trials have produced evidence in favour of this recommendation. Objective Our objective was to assess human milk ovalbumin (OVA) concentration after daily maternal ingestion of one cooked egg for 3 weeks. Methods Mothers with egg‐sensitive, eczematous breastfed infants were randomly allocated to consume one muffin per day containing one egg (egg group, n=16) or a similar egg‐free muffin (control group, n=16) for 21 days (Days 3–23). All mothers and infants followed an egg‐free diet. Breast milk samples were collected at two hourly intervals for 6 h after eating the test muffins on Days 3, 12 and 23 and breast milk OVA concentration measured. Infant eczema was assessed at the commencement and completion of the trial. Results Women in the egg group had higher OVA concentrations in breast milk than the control group at all time‐points. Within each dietary group, OVA excretion did not change with time. OVA was not detected in breast milk of 25% of women in the egg group. In contrast, infant eczema symptom scores significantly reduced with time for both groups. Conclusion Human milk OVA is related to maternal dietary egg intake, but a significant proportion of women either have a delayed excretion or may not excrete OVA in their breast milk.