Post-breastfeeding stress response and breastfeeding self-efficacy as modifiable predictors of exclusive breastfeeding at 3months postpartum: a prospective cohort study

BackgroundThe rate of exclusive breastfeeding at 3months postpartum is only 50% in Japan. In order to increase this rate, we aimed to examine modifiable factors related to exclusive breastfeeding at 3months postpartum by focusing on breastfeeding-related and psychosocial variables at 1month postpartum.MethodsThis prospective cohort study was conducted at a secondary medical care center in Osaka, Japan from February 2017 to October 2018. Demographic variables, infant feeding modality, breastfeeding-related variables, and psychosocial variables were obtained using questionnaires at 1month postpartum. Daytime salivary cortisol levels before and after breastfeeding at 1month postpartum were measured as a biological marker for stress responses associated with breastfeeding. Each infant's feeding modality was re-assessed at 3months postpartum. Multiple logistic regression analyses were performed to examine factors affecting exclusive breastfeeding at 3months postpartum.ResultsOf the 104 participants, 61 reported exclusive breastfeeding at 3months postpartum. The following factors were significantly associated with exclusive breastfeeding at 3months postpartum: multiparity (adjusted odds ratio, 95% confidence interval: 11.13, 2.08-59.59), having a university degree (5.25, 1.04-26.53), no plan to return to work by 6months postpartum (0.02, 0.00-0.46), and exclusive breastfeeding (42.84, 6.05-303.52), lower cortisol level after breastfeeding (0.00, 0.00-0.02), and higher breastfeeding self-efficacy scale score (1.07, 1.00-1.14) at 1month postpartum. In parity-specific analyses, exclusive breastfeeding (25.33, 4.75-134.98) and lower cortisol level after breastfeeding (0.00, 0.00-0.21) at 1month postpartum in primiparous women, and lower cortisol level after breastfeeding (0.00, 0.00-0.94), higher breastfeeding self-efficacy score (1.18, 1.05-1.32), and absence of breast complications (0.09, 0.01-0.82) at 1month postpartum in multiparous women were associated with exclusive breastfeeding at 3months postpartum.ConclusionsStress levels after breastfeeding, breastfeeding self-efficacy, and the presence of breast complications could be modifiable factors associated with subsequent exclusive breastfeeding. Further research is needed to examine whether approaches to reducing breastfeeding-related stress, improving breastfeeding self-efficacy, and preventing breast complications during lactation are effective to increase exclusive breastfeeding practices.