[Infant breastfeeding prevalence in the city of São Paulo, Brazil, 2008].

This cross-sectional epidemiological study based on AMAMUNIC aimed to evaluate infant breastfeeding (BF) prevalence and duration in São Paulo, Brazil. Sample size was based on a cluster calculation, selecting 35 primary care units and 35 infants (< 1 year of age) per unit. A total of 1,424 interviews with mothers were performed (56 items on feeding in the previous 24 hours) in August 2008, subsequently analyzed according to residential areas: Central West, East, North, Southeast, and South. Prevalence of exclusive breastfeeding (EBF) was 52% up to three months and 39% up to six months, as follows: 44% (Central West), 57% (East), 62% (North), 43% (Southeast), and 48% (South) up to three months and 36% (Central West), 46% (East), 39% (North), 36% (Southeast), and 33% (South) up to six months. Prevalence of EBF according to infant age was 58% in the first month, 50% in the second and third, and 13% in the sixth. In conclusion, EBF prevalence up to six months is still heterogeneous in the city, suggesting the need for programs to encourage BF that are differentiated according to region.