OBJECTIVE: Data on the prevalence and predictors of breast-feeding remain scarce in Lebanon. Moreover, no study has previously addressed the effect of the paediatrician's sex on breast-feeding. The present study aimed to assess the prevalence and predictors of breast-feeding at 1 and 4 months of infant age while exploring the potential role of the sex of the paediatrician. DESIGN: Prospective cohort study. Predictors of breast-feeding significant at the bivariate level were tested at 1 and 4 months through two stepwise regression models. SETTING: Infants were enrolled through the clinics and dispensaries of 117 paediatricians located in Beirut, Lebanon, and its suburbs. SUBJECTS: A total of 1,320 healthy newborn infants born between August 2001 and February 2002 were prospectively followed during the first year. FINDINGS: Breast-feeding rates at 1 and 4 months were 56.3 % and 24.7 %, respectively. Early discharge, high parity and religion were significantly associated with higher breast-feeding rates at 1 and 4 months of age. Maternal age proved significant only at 1 month, while maternal working status and sex of the paediatrician were significant at 4 months. A novel finding of our study was the positive effect of female paediatricians on breast-feeding continuation until 4 months of age (OR = 1.49; 95 % CI 1.03, 2.15). CONCLUSIONS: Breast-feeding rates are low at 1 and 4 months of infant age in Beirut. Further research to investigate the interactions between female physicians and lactating mothers in maintaining breast-feeding in other populations is warranted. The results constitute the basis for designing interventions targeting policy makers, health professionals and mothers.