[Immigration and factors associated with breastfeeding. CALINA study].

OBJECTIVE To identify socio-cultural, obstetric and perinatal characteristics associated with complete breastfeeding (CBF) during the first 4 months of age, depending on maternal origin. MATERIAL AND METHODS Socio-cultural, obstetric and perinatal aspects associated with breastfeeding depending on maternal origin were evaluated in a longitudinal study in a representative infant population from Aragon (n = 1452). RESULTS The prevalence of CBF was higher in immigrant mothers than in those from Spain. CBF was maintained in 37.2% of mothers from Spain at 4 months, compared with 43% of immigrants (P=.039) (RR Spanish/immigrants=0.76; 95% CI: 0.58-0.99); at 6 months this occurred in 13.9% vs. 23.8%, respectively (P<.001) (RR Spanish/immigrants=0.52; 95% CI: 0.37-0.72). The factors associated with CBF at 4 months are different between both groups. Mothers born in Spain are older (P=.002), have higher academic level (P=.001), greater parity (P=.003), and a higher probability of vaginal delivery (P=.005); and their children have the highest anthropometric values at birth. However, in immigrant mothers, the maintenance of CBF was associated with a higher maternal body mass index and with working at home. In both groups, CBF remains more frequently in those mothers who do not smoke (P=.001). CONCLUSIONS The prevalence of CBF during the first months of life is higher in immigrant mothers than in those from Spain, and socio-cultural, obstetric and perinatal factors are different, depending on maternal origin.