RESUMO
Objectives: This study examined specificity in the effects of three perinatal mindfulness-based prevention programs that differed in their timing (prenatal, postpartum) and target (maternal well-being, parenting). Effects on maternal mental health (depression, anxiety, resilience), mindfulness, and observed parenting, as well as observed, physiological, and mother-report indicators of infant self-regulation, were examined. Methods: The programs were evaluated in a racially and ethnically diverse sample of first-time mothers (n = 188) living in low-income contexts using intention-to-treat analysis. Mothers were assigned to a prenatal well-being, postpartum well-being, parenting, or book control group. Multi-method assessments that included questionnaire, observational, and physiological measures were conducted at four time points: during pregnancy (T1) and when infants were 2-4 months (T2), 4-6 months (T3), and 10-12 months. Results: Compared to the postpartum intervention and control groups, the 6-week prenatal well-being intervention was related to decreases in depressive symptoms during pregnancy but not postpartum, higher maternal baseline respiratory sinus arrhythmia (RSA), fewer intrusive control behaviors, and lower infant cortisol levels in the early postpartum period. Compared to all other groups, the postpartum parenting intervention was related to decreases in maternal anxiety and increases in responsive parenting. Some differential effects across programs might be due to differences in attendance rates in the prenatal (62%) vs. postpartum (35%) groups. Conclusions: The findings suggest that brief mindfulness-based well-being and parenting preventive interventions can promote maternal and infant mental health in families living in low-income, high-stress settings, particularly if accessibility can be enhanced. Preregistration: This study is not preregistered.