This study aimed to investigate the relative importance of the psychosocial factors underlying mother’s decision to continue exclusive breastfeeding (EBF) for 6 months using the theory of planned behavior. A cohort of EBF-mothers (N = 78) completed a questionnaire assessing theoretical constructs at baseline and phone-interviewed at follow-up. Multiple regression analyses were performed to find important predictors of intention, overall and married vs unmarried. Attitude, subjective norm, and perceived behavioral control together explained 50.2% (P < .01) of the variance in mothers’ intention to continue EBF for 6 months. Attitude and subjective norm were better predictors of the intention than perceived behavioral control. The role of subjective norm was greater in married than in unmarried women. A strong, positive correlation (γ = 0.67, P < .01) was found between intended and actual EBF duration. Intervention programs designed to positively influence mother’s attitude and social support may be effective in improving intention, thereby increasing EBF maintenance for 6 months. J Hum Lact. 26(1):26-34.

Background: Numerous efforts to promote breastfeeding resulted in a steady increase in the rates of breastfeeding initiation and duration. Increasing numbers of breastfeeding interventions are focused on breastfeeding maintenance and exclusivity and based on behavioral theories. Few studies critically analyzed the use of theories in breastfeeding intervention development and evaluation. Research aim: The aim of this critical review was to examine the existing literature about breastfeeding intervention, and investigate the role of theory in its development, implementation, and evaluation to provide future directions and implications for breastfeeding interventions. Methods: This critical review examined the existing breastfeeding intervention studies that used self-efficacy theories (SE), theory of planned behavior (TPB), and social cognitive theory (SCT) and were published during the past decade. Using five databases, studies in which researchers explicitly applied these three theories to frame the intervention were selected. Studies were critically reviewed for fidelity to theory in intervention design, delivery, and evaluation. Results: Eighteen studies were reviewed: nine SE-, five TPB-, and four SCT-based. Most interventions were focused on building mothers’ breastfeeding self-efficacy to improve breastfeeding exclusivity and duration. To achieve this goal, researchers who developed SE-based interventions used individual approaches, whereas other researchers who based studies on TPB incorporated social and environmental changes. SE-based studies were more likely to include theory-based instruments, but TPB- and SCT-based studies demonstrated less consistent choices of measurement. Researchers in most studies did not test the relationships between the proposed theoretical constructs and breastfeeding outcomes as guided by theories. Inconsistent outcomes resulted among the studies due to variations in study follow-ups. Conclusion: Sound applications of single or multiple theories demonstrate a great potential to help practitioners and researchers develop effective breastfeeding interventions and evaluate true impacts on positive breastfeeding outcomes.