The effect of breastfeeding on reducing pain induced by pentavalent vaccine in infants: a randomized clinical trial.

Objective: To analyze the effect of breastfeeding on reducing Pentavalent vaccination pain in infants and to identify the necessary breastfeeding interval for antinociceptive action.

Method: Open parallel randomized clinical trial. Ninety mother-infant dyads participated, distributed into intervention group 1 (n = 30), which breastfed five minutes before vaccination; intervention group 2 (n = 30), which breastfed five minutes before and during vaccination; and control group (n = 30), which did not breastfeed.