The effect of infant formula samples on breastfeeding practice.

To determine whether infant formula samples affect breastfeeding practice, 95 breastfeeding mothers were randomly assigned to receive or not receive formula samples on discharge from a postpartum unit. Unaware of the specific nature of the study, these mothers were interviewed by telephone six to seven weeks postpartum by an investigator blind to the randomization status. Although more women who had discontinued breastfeeding were among the group who had received samples than those who had not received samples, the difference was not statistically significant. Significant differences were not found in three subgroups hypothesized to be more vulnerable to the samples: less educated women, primiparas, and women who were ill postpartum.