Religion and spirituality are major forces in the lives of Americans and are especially salient for women and families in the time surrounding the birth of a child. A large and growing body of research indicates that specific aspects of religiousness and spirituality are associated with better physical and mental health. However, the mechanisms of these associations are not well understood, though many have been hypothesized. The hypothesized mechanisms are reviewed to develop a conceptual model of religiousness, spirituality, physical and mental health, and their mechanisms and empirical evidence supporting these pathways is examined. This conceptual model provides the basis for several hypotheses tested in three studies which examined associations of religiousness and spirituality, together and separately, with three markers of health: depressive symptoms, the inflammatory marker, C-reactive protein, and the diurnal slopes of the stress hormone, cortisol, and tested psychosocial resources as a mechanism of these associations in a large sample of postpartum women. Psychosocial resources and the religiousness and spirituality constructs were operationalized with multiple measures and tested in a study of low income postpartum women who were of diverse ethnicity.

Results indicated that psychosocial resources composed of indices of mastery, self-esteem and optimism were associated with religiousness and spirituality. Furthermore, religiousness and spirituality were associated with depressive symptoms and C-reactive protein, but not diurnal cortisol slope. In particular, higher religiousness and spirituality both together and separately predicted lower depressive symptoms throughout the first year postpartum. Higher religiousness and spirituality together and spirituality alone predicted lower C-reactive protein at six months postpartum. The psychosocial resource factor composed of mastery, self-esteem, and optimism mediated the associations of religiousness and spirituality with depressive symptoms, but not of associations of religiousness and spirituality with C-reactive protein. These findings contribute substantially to existing knowledge by demonstrating a link between spirituality and inflammation for the first time, and regarding psychological resources as mechanisms of associations of religiousness, spirituality, and health-related outcomes. These findings can guide future research on associations of religiousness, spirituality, and health and their mechanisms.