The Multiple Mediating Effects of Internalized Weight Stigma, Breastfeeding Difficulties, and Breastfeeding Self-Efficacy on the Association Between Pre-pregnancy Overweight/Obesity and Exclusive Breastfeeding at 6 Months Postpartum: A Prospective Cohort Study

Background Despite the World Health Organization's (WHO) emphasis on the essential role of exclusive breastfeeding for both maternal and infant health, exclusive breastfeeding rates among women with pre-pregnancy overweight/obesity remain suboptimal. The underlying mechanisms driving this negative association are not well-understood. This study aimed to explore these mechanisms by examining the independent and sequential mediation effects of internalized weight stigma, breastfeeding difficulties, and breastfeeding self-efficacy on the relationship between pre-pregnancy overweight/obesity and exclusive breastfeeding at six months postpartum. Methods In this prospective cohort study, 296 primiparous women were stratified by pre-pregnancy body mass index (BMI) into two groups: pre-pregnancy overweight/obese (n = 146) and normal BMI (n = 150). Data were collected via questionnaires during the antenatal period and at 6 months postpartum. After adjusting for covariates, structural equation modeling with maximum likelihood estimation was utilized, along with bias-corrected bootstrap testing, to estimate and assess the mediation effects in the negative association between maternal pre-pregnancy overweight/obesity and exclusive breastfeeding at 6 months postpartum. Results The study confirmed a negative correlation between pre-pregnancy overweight/obesity and exclusive breastfeeding at 6 months postpartum. Significant indirect paths were identified from pre-pregnancy overweight/obesity to exclusive breastfeeding at 6 months postpartum through internalized weight stigma (β = −0.217, p = 0.001), breastfeeding difficulties (β = −0.078, p = 0.018), and breastfeeding self-efficacy (β = −0.052, p = 0.025), each contributing separately. Additionally, a significant indirect path was found through the serial mediation of breastfeeding difficulties and breastfeeding self-efficacy (β = −0.053, p = 0.001). Conclusions This study elucidated the complex relationship between pre-pregnancy overweight/obesity and reduced exclusive breastfeeding rates at 6 months postpartum, identifying internalized weight stigma, breastfeeding difficulties, and decreased breastfeeding self-efficacy as significant mediating factors. Future research should concentrate on developing targeted interventions to overcome these obstacles, potentially including psychological therapies, hands-on breastfeeding support, and self-efficacy enhancement. Trial registration This study was registered at the Chinese Clinical Trial Registry (http://www.chictr.org.cn/, registry number: ChiCTR2200057038). The trial registration date was (26/02/2022).