Coo, SoledadBennett Escalona, Ana Flavia2026-08-172026-08-172026https://hdl.handle.net/11447/11016Thesis submitted to the Faculty of Psychology of the Universidad del Desarrollo for the academic degree of Doctor in Developmental Sciences and PsychopathologyIntroduction. The transition to parenthood constitutes a critical period demanding substantial individual and family adjustments. Parental self-efficacy—the beliefs parents hold about their capacity to perform the parental role—is a fundamental resource for successful adaptation to parenthood. Interparental relationships, particularly couple satisfaction and coparenting, emerge as key relational contexts for its development. However, evidence on how these processes unfold longitudinally in mothers and fathers during the perinatal period remains limited. Objective. The study assessed the contribution of interparental relationships during the transition to parenthood on parental self-efficacy at 6 months postpartum, evaluated as a general domain and as developmental stage-specific tasks, in both parents. Method. Participants were 234 Chilean couples assessed at three time points: third trimester of pregnancy, three months postpartum, and six months postpartum. Measures included couple satisfaction (DAS), coparenting (CRS), general-domain (EEP) and task-specific (KPCS) parental self-efficacy, and depressive symptoms (BDI). Sequential mediation models with multigroup analysis for dyadic data and an Actor-Partner Interdependence Model (APIM) were implemented. Results. Coparenting at three months predicted parental self-efficacy at six months in both parents, with a stronger effect for fathers on task-specific self-efficacy. Coparenting mediated the relationship between prenatal couple satisfaction and postpartum parental self-efficacy, with gender differences in the magnitude. The APIM revealed significant actor effects from coparenting on parental self-efficacy at six month postpartum for both parents, but no partner effects were found. Discussion. Findings highlight the role of coparenting as a central mechanism in the association between couple satisfaction and parental self-efficacy. The stronger influence on fathers suggests that, in contexts where mothers are the primary caregivers, coparenting constitutes a particularly relevant pathway for developing paternal self-efficacy. Results underscore the importance of interventions that strengthen family processes as a resource for both parents during the perinatal period and include fathers in perinatal care.236 p.enParental self-efficacyCoparentingCouple satisfactionTransition to parenthoodThesishttps://doi.org/10.52611/11447/11016