BACKGROUND: Identifying the behavioral determinants of breastfeeding is an important step toward increasing breastfeeding rates, but studies often adopt a limited measurement model. We aimed to identify, in a British population, which behavioral and psychological factors, assessed throughout the perinatal period, were most reliably associated with intent to breastfeed and breastfeeding at 1 and 6 months. METHODS: This is an observational longitudinal study of a diverse (35.1% non-white) community sample of N = 222 pregnant women attending a maternity hospital in the UK. We assessed self-reported anxiety and depressive symptoms, stressful life events, and coping at 20-22, 28 and 36 weeks gestation and 1 and 6 months postnatally
intention to breastfeed was assessed at 20 weeks gestation. Breastfeeding was assessed at one and six months post-partum. We modelled the associations with logistic regressions, adjusting for socio-demographics. RESULTS: Antenatal and post-partum depressive and anxiety symptoms were not reliably associated with breastfeeding behavior up to 6 months. In contrast, breastfeeding intention, which was not associated with affective symptoms, stress, and coping, was a reliable predictor of breastfeeding after adjusting for covariates. The association between intention to breastfeed and breastfeeding behavior was not moderated by behavioral/psychological factors (p >
0.5). CONCLUSIONS: This study extends previous findings about the importance of intention to breastfeed to breastfeeding behaviour and suggests that suffering from affective symptoms does not inhibit breastfeeding. Antenatal intention to breastfeed can play a crucial role in shaping both maternal and child health outcomes.