The objective of our study was to identify factors associated with the initiation of breast-feeding in a poor urban area. One hundred postpartum, nonadolescent, non-drug using mothers, 50 breast-feeding and 50 formula feeding, were consecutively interviewed. Breast-feeding women were more likely to be born outside of the United States (42 versus 14%, p = 0.002), have more years of education (12.1 +/- 1.9 versus 10.9 +/- 1.7, p = 0.002), be employed either prior to or during pregnancy (38 versus 16%, p = 0.000), be married (46 versus 26%, p = 0.037), be a nonsmoker (86 versus 64%, p = 0.011), have more prenatal visits (8.4 +/- 7.3 versus 5.0 +/- 5.9, p = 0.010), or have a breast-feeding mother (48 versus 26%, p = 0.023). There were no differences in age or ethnicity. The father of the breast-feeding baby was more likely to be better educated (12.0 +/- 2.8 versus 10.5 +/- 3.6 years, p = 0.022) and to work full-time (68 versus 40%, p = 0.005). Eighty-four percent of formula feeders knew that breast milk was better for their babies but decided not to breast-feed due to concerns of pain, smoking, and work. Sixty-three percent of women made the choice to breast-feed prior to the pregnancy, 26% during the pregnancy, and 11% after delivery. Significantly more multiparas decided prior to the pregnancy compared with primaparas. We recommend that breast-feeding education should be started prior to the first pregnancy and tailored to the concerns of the women.