Data from a national survey of new mothers were analyzed to determine the effect that demographic characteristics, breast-feeding instructions, and infant formula discharge kits had on breast-feeding patterns established in the hospital. Results indicated that mothers who exclusively breast-fed their infant were more likely to be affluent, college educated, and not working outside the home. Mothers who exclusively breast-fed their infants in the hospital and subsequently practiced partial breast-feeding or formula, or cow's milk feeding were more likely to return to the work force within the first 6 postpartum months. Mothers who partially breast-fed their infants in the hospital were more likely to have a low-birth-weight neonate. Stepwise logistic regression analysis indicated that greater total family income, a better education, and having more than one child had positive significant effects on exclusive breast-feeding by the first and fourth month. Women who received a formula discharge kit compared with those who did not had a slightly higher probability of initiating partial breast-feeding (10 vs. 7% by the first month; 27 vs. 25% by the fourth month). Maternal employment had a large impact on duration of exclusive breast-feeding. By the fourth month, mothers who were employed had a higher probability of initiating partial breast-feeding (43 vs. 19%) compared with mothers who were not in the work force.