Demographic characteristics of the subjects, their mothers, and their household by distance from a health center (n = 12345).

no., number; SD, standard deviation.The total number of subjects and percentages may not sum correctly owing to rounding and missing data.aThe percentage is obtained by dividing the number of participants by the total number of births, stratified according to distance to a health center.bWealth was calculated based on tertile category of wealth score within country.