Fig. 3.

Kaplan-Meier plots depicting the proportion of infants who remained antibiotic-free over the first 3 years of life stratified according to whether they were breast-fed, cow’s milk formula fed, or soy infant formula fed during the first year^1,2,3. ¹Values represent the fraction of breast-fed, cow’s milk formula–fed, or soy formula–fed infants not treated by antibiotics at any one visit over the time course of the study. ²Data represent all measurements for each variable at each time point for all infants attending the visit. ³Statistics: χ² test was performed at each age to evaluate the association between antibiotic use and equol production. No significant association was found when all food groups were combined for each age, except for age 36 months, where there was a lower percentage of equol producers in infants who received antibiotics. When the association was evaluated for each age group within each nutrition group, no significant associations were observed.