Socio-economic status and maternal BMI are associated with duration of breast-feeding of Norwegian infants.

OBJECTIVE: To explore whether there is an association between socio-economic status and maternal BMI and duration of any breast-feeding/exclusive breast-feeding among Norwegian infants at 4 and 5 months of age in 2016.

DESIGN: Cross-sectional design. Baseline data from a randomized controlled trial. Data concerning breast-feeding were collected by FFQ.

SETTING: Recruitment was done at child health-care centres and through Facebook in 2016. In total, 960 infants/parents registered for participating in the study Early Food for Future Health.

SUBJECTS: A total of 715 infant/mother dyads completed the questionnaire when the child was between 5 and 6 months old.

RESULTS: At 5 months of age, 81·0 % of infants were breast-fed and 16·4 % were exclusively breast-fed. Infants of highly educated mothers had higher odds of being breast-fed at 5 months compared with infants of mothers with less education. Infants of multiparous mothers had higher odds of being exclusively breast-fed for the first 5 months compared with infants of mothers with one child. Infants of mothers with overweight/obesity had reduced odds of both being breast-fed at all and being exclusively breast-fed at 4 months of age compared with infants of mothers with normal BMI.

CONCLUSIONS: Our results show that duration of breast-feeding varies with socio-economic status and maternal BMI in Norway. Targeting groups with low socio-economic status and mothers with overweight or obesity is important, as they are less likely to breast-feed according to recommendations.