Exclusive breastfeeding practices reported by mothers and the introduction of additional liquids.

Aim: To assess the concept of exclusive breastfeeding held by nursing women by comparing the period they consider that they perform it and the infants' age at the introduction of additional liquids.

Method: Cross-sectional descriptive study conducted with 309 women who delivered babies at a university hospital in the interior of São Paulo, Brazil. The data were subjected to descriptive analysis; the variables of interest were crossed using the non-parametric Kruskal-Wallis test, the chi-square test and Fisher's exact test.