Daughters et al. (2023) The relationship between maternal oxytocin concentrations, maternal mental health and parenting

The evolutionary conserved neuropeptide oxytocin (OT) has been found to support adaptive parenting behaviour. Previous research has demonstrated that parenting behaviour can have an enduring effect on their children’s oxytocin responses and subsequent behaviour. It is therefore crucial to understand under what circumstances and for whom the important relationship between OT and parenting behaviour may be disrupted. The present study directly assessed the impact of maternal mental health on the relationship between OT and mother-infant interaction during both a high- and low-stress challenge. Seventy-seven mothers from the Grown in Wales project self-reported their mental health prenatally and postnatally 12 months later when they took part in a behavioural assessment with their infant. Mothers provided three saliva samples during the assessment to measure their OT concentrations. OT was measured using radioimmunoassay on extracted samples. We hypothesised a negative relation between maternal mental health and OT concentrations and a positive relation between quality of mother-infant interactions and mothers’ OT responses. For low-risk (no prenatal mental health disorders) mothers, prenatal anxiety was associated with lower baseline OT concentrations. There was also a positive relation between OT response and mother-infant interaction for low-risk mothers during the high-stress separation and reunion task; high-risk (with prenatal mental health disorders) mothers demonstrated a negative relation whereby greater OT responses were associated with poorer mother-infant interaction. Results cautiously suggest that the important relationship between OT and adaptive parenting is disrupted by mental health disorders.