Associations between body mass index estimated using the self-reported body weight at about 20 years of age and each index of breastfeeding history.

Abbreviations: OR, odds ratio; CI, confidence interval. a All the indices of breastfeeding history were defined and categorized in the same way as in Tables 1 and 2. b Higher categories of breastfeeding history were as follows in all participants, those c Models incorporated the same covariates as those of multivariable-adjusted models in Table 2 in the analyses of the longest and the total breastfeeding duration. In the analyses of the number of breastfed children, models incorporated the same covariates except for parity. d Odds ratios and 95% CIs were calculated using the unconditional binary logistic regression model. (XLSX)