The aim of this study was to assess the association between exclusive breastfeeding (EBF) and some factors that may influence breastfeeding in a closely related population attending a private hospital sponsored by a major Mexican brewing company. We carried out a retrospective hospital-based unmatched case-control study. A sample of 124 mother-newborn couples was interviewed in a private medical unit in Monterrey, Mexico, from January 2001 to January 2002. The association between EBF and 11 explanatory factors was analyzed by logistic regression analysis. Counseling and early contact between mother-newborn couples were positively associated with EBF. Counseling and early contact improve EBF practice. We believe these two practices would favor better adherence to EBF in other populations.