To what extent does maternal body mass index predict intentions, attitudes, or practices of early infant feeding?

Public health guidelines recommend women establish and maintain exclusive breastfeeding to 6 months postpartum. Women with a body mass index (BMI, kg/m2 ) in the overweight or obese range are less likely to initiate and continue breastfeeding than healthy weight women. Evidence for psychological mechanisms of this association using validated methods of measurement is limited, but factors such as attitudes and intentions for infant feeding are implicated. This study aimed to investigate the associations between maternal BMI, antenatal attitudes and intentions for infant feeding, and subsequent breastfeeding practices. A total of N = 128 women completed an online questionnaire antenatally, and n = 48 were followed-up in the first month postpartum. Validated measures of intentions (Infant Feeding Intentions Scale) and attitudes (Iowa Infant Feeding Attitude Scale) for infant feeding were used. One-way analysis of variance and multivariate regression analyses assessed study objectives. Infant feeding attitudes (p = .327) and intentions (p = .254) were similar among healthy weight, overweight, and obese women and did not differ significantly. In adjusted regression models, only intentions significantly predicted early breastfeeding behaviour (p = .036; AR2  = .301). Missing data analysis revealed no significant differences in the profile of completing versus noncompleting women. Evidence suggests postnatal factors contribute significantly to lower breastfeeding rates in cohorts of women with overweight or obese BMIs. Further investigations should consider using theory and methods from behavioural science to longitudinally investigate modifiable mechanisms of action responsible for lower breastfeeding rates among overweight and obese women to inform practices that support prolonged breastfeeding.