Role of Maternal Mindfulness in Longitudinal Mother-Infant Neuroendocrine Reciprocity in an Urban, Low-Income White Sample.

Mother-infant physiological reciprocity plays a crucial role in child well-being and development. While mindfulness in parenting has been linked to mother-infant stress responses, no research has examined its relationship with developmental trajectories of neuroendocrine reciprocity. This study addresses this gap by examining maternal mindfulness-both alone and in the context of parenting risk and protective factors-in relation to mother-infant cortisol reciprocity over time. Using data from 56 predominantly White, urban, low-income mother-infant dyads in the United States followed from 3 to 18 months postpartum, we tested maternal mindful parenting at 3 months as a predictor of both (1) within-session reciprocity of mother and infant cortisol responses to acute stress and (2) across-session reciprocity of developmental shifts in their cortisol levels from 6 to 18 months. Three-level hierarchical linear models revealed that higher maternal mindful parenting, greater history of positive parental bonding, and lower parenting stress were associated with more inverse mother-infant cortisol reciprocity across timepoints. In addition, parenting stress moderated the effect of mindful parenting: the inverse relation with reciprocity held for most dyads (60%), though reversed for those with the highest stress levels (top 9%). Findings delineate when and how positive versus inverse reciprocity may be adaptive and underscore the role of mindful parenting in mother-infant psychophysiological stress co-adaptation.