purpose: to investigate the association among types of breastfeeding, presence of child development risk, socioeconomic and obstetric variables. methods: the sample was composed of 182 mother-child dyades. data were collected through an initial interview about breastfeeding; obstetric, socioeconomic, demographic and psychosocial aspects; and mother-child interaction analysis by the child development risk inventory. the data were organized in categories related to breastfeeding, presence or absence of child development risk, obstetric and socioeconomic variables, and were analyzed in statistica 9.0 software for statistical analysis. results: the mixed breastfeeding type shows statistical correlation between presence of child development risk as well as to variables such as prematurity, low weight, birth intercurrences and mother's domestic profession. conclusion: the results show that factors such as low weight, prematurity and presence of birth intercurrences can be associated to mixed breastfeeding, even if the mothers present physical and time availability for breastfeeding. these variables can be associated to mother-child initial interactions detected by child development risk inventory.