A randomised controlled trial evaluating the effect of a brief motivational intervention to promote breastfeeding in postpartum depression

Postpartum depression (PPD) is the most frequent psychiatric complication during the postnatal period. According to existing evidence, an association exists between the development of PPD and the maintenance of breastfeeding. A brief motivational intervention (bMI), based on the motivational interview, seems effective in promoting breastfeeding. The objective of this study was to analyse the impact of a bMI aiming to promote breastfeeding on the development of PPD and explore the mediating/moderating roles of breastfeeding and breastfeeding self-efficacy in the effect of the intervention on developing PPD. Eighty-eight women who gave birth by vaginal delivery and started breastfeeding during the immediate postpartum period were randomly assigned to the intervention group (bMI) or control group (breastfeeding education). Randomisation by minimisation was carried out. The breastfeeding duration was longer in the intervention group (11.06 (± 2.94) weeks vs 9.02 (± 4.44), p = 0.013). The bMI was associated with a lower score on the Edinburgh Postnatal Depression Scale, with a regression β coefficient of − 2.12 (95% CI − 3.82; − 0.41). A part of this effect was mediated by the effect of the intervention on the duration of breastfeeding (mediation/moderation index β = − 0.57 (95% CI − 1.30; − 0.04)). These findings suggest that a bMI aiming to promote breastfeeding has a positive impact preventing PPD mainly due to its effectiveness in increasing the duration of breastfeeding.