A mother’s emotional state is a well-known environmental factor that relates to the development of infant temperament. However, some relevant issues have not yet been fully explored. The current study examines the influence of determined maternal, contextual and perinatal variables on infant temperament and the mother’s confidence in caregiving during the first weeks of life. A prospective study was carried out in three-hundred and seventeen newborns and their mothers. Perinatal and socio-demographic variables were recorded. The mother’s anxiety and mood were measured in the first days after childbirth and again at 8 weeks. Infant temperament and the mother’s confidence in caregiving were measured at 8 weeks. A mother’s postpartum anxiety following delivery was the best predictor for most of the variables of infant temperament, including infant irritability (p = .001), and other child variables like infant sleep (p = .0003) and nursing difficulty (p = .001). Contextual-family variables, such as the number of people at home (p = .0024) and whether they were primiparous (p = .001), were the best predictors for a mother´s confidence in caregiving. Support was found for an early effect of maternal anxiety on infant temperament. The results have clinical implications for postnatal psychological interventions.