A Longitudinal Study of the Stress-buffering Effect of Social Support on Postpartum Depression

Abstract Background: Postpartum depression (PPD) impacts about one out of eight new mothers, and it has a unique and pervasive impact on a woman, a child, and a family. Research has demonstrated that perceived social support has a positive effect on PPD. Nevertheless, there has been disagreement on how social support influences depression. The overall goal of this study is to test the stress-buffering effect of social support on postpartum depression by using two different definitions of stress and following a rigorous procedure of research design and statistical analyses. Methods: Secondary longitudinal data were used to answer the research question. In total, 512 first-time mothers comprised the study sample. Parenting stress and difficult life circumstances measured at six months postpartum was used to predict the changes in depressive symptoms from 6 to 12 months postpartum and social support measured at six months postpartum was used as a moderator between stress and PPD. Structural Equation Modeling (SEM) was adopted for statistical analyses. Results: The results showed that parental distress, one component of parenting stress, had a significant long-lasting impact on PPD. The other two components of parenting stress, difficult child and parent-child dysfunctional interaction, did not have a direct effect on PPD. Difficult life circumstance also showed a significant enduring influence on PPD. Social support was not found to moderate the influence of parenting stress or difficult life circumstances on PPD. A significant direct effect of social support on depression was not found by this study either. Neither the stress-buffering theory of social support nor the main-effect model of social support was endorsed by the longitudinal study. Conclusions: The findings encourage social workers to be mindful of the impact of parental distress and difficult life circumstances on new mothers’ mental health. Problem-solving tools and interventions that aimed to enhance self-mastery and self-efficacy are recommended to help new mothers be more resilient in dealing with parental distress and daily hassles. Measures for social support and parenting stress with higher capability of discrimination should be used in future stress-buffering research. More longitudinal studies with shorter lags between measurement occasions are warranted in order to figure out at what point social support is most useful for new mothers’ mental health.