Introduction: Breast milk is the main source of nourishment for the healthy growth and development of newborns up do six months, and after that, it serves as a supplement up to two years. The act of breastfeeding, in addition to being an important means of forming an affective bond between the mother and infant, also promotes maternal, social and environmental benefits. Although its importance has been proven, it is known that there are several reasons that lead to the early interruption of breastfeeding, including breast complications. Our aim was to determine the incidence of complications related to breastfeeding in puerperal women seen at Hospital Regional, a philanthropic hospital in Presidente Prudente (SP) and the possible factors that led to their appearance as well. Methods: A quantitative-qualitative longitudinal study was carried out with puerperal women cared for at Hospital Regional of Presidente Prudente. A structured interview was administered in three stages: the first during the puerperal women’s hospitalization and the others, through telephone contact at respectively 30 and 90 days after delivery, to monitor breastfeeding. Results: Of the total number of patients interviewed, 24.3% had some breast complications resulting from breastfeeding. Still in the immediate postpartum period at 30 days, this proportion reached 42.23%, decreasing at 90 days to 17.47%. Furthermore, of the puerperal women that showed any complication, 74% of them were single, 54% had brown skin color, 42.9% had completed high school and 52% were primiparous. Moreover, the patients who had a Cesarean section (53,8%) showed more complications than the ones who had natural childbirth (35,1%). Conclusions: The main breast complications found were nipple fissure, breast engorgement, milk retention nodules and mastitis.