1 Department of Psychiatry, McGill University, 1033 Pine Ave W, Montreal, Quebec, H3A 1A1, Canada.
2 Department of Psychology, Concordia University, 7141 Sherbrooke St W, Montréal, Quebec, H4B 1R6, Canada; Center for Clinical Research in Health, Concordia University, 7141 Sherbrooke St W, Montréal, Quebec, H4B 1R6, Canada.
3 Department of Psychology, McGill University Health Centre, 1025 Pine Avenue West, Montréal, Quebec, H3A 1A1, Canada.
4 Department of Psychology, Concordia University, 7141 Sherbrooke St W, Montréal, Quebec, H4B 1R6, Canada; Center for Clinical Research in Health, Concordia University, 7141 Sherbrooke St W, Montréal, Quebec, H4B 1R6, Canada; PERFORM Center, Concordia University, 7141 Sherbrooke St W, Montréal, Quebec, H4B 1R6, Canada. Electronic address: jp.gouin@concordia.ca.

Objective: A parent's ability to self-regulate influences parenting practices. Child-related stressors may deplete parent's self-regulatory capacities. However, this effect may be moderated by the marital context within which stressful parent-child interactions are occurring. The aim of the current study was to investigate the association between child behavioural problems and parent vagally-mediated heart rate variability (vmHRV), a psychophysiological index proposed to index self-regulatory capacities, and to test whether marital stress moderated this effect.

Methods: Eighty cohabiting heterosexual couples with preschool children had their vmHRV recorded during a laboratory session and completed a measure of child behavioural problems. Daily assessments of marital stress were measured over six consecutive days. Partner's ratings of child behavioural problems and marital stress were used to predict participant's vmHRV.

Results: After adjusting for participant's age, gender, and ethnicity, greater child behavioural problems predicted lower parent vmHRV. Marital stress exacerbated the association between child behavioural problems and parent vmHRV. However, this association was moderated by parent's gender, with marital stress exacerbating the association between child behavioural problems and parent vmHRV for fathers, but not for mothers.

Conclusion: Child-related stressors are associated with reduced self-regulatory capacities among parents of preschool children as assessed by vmHRV. Fathers are especially vulnerable to the marital context within which these stressors are occurring. Poor self-regulation capacities during the early parenting years may place both parents and children at risk for long-term maladaptive outcomes.