| Approximately 25% of women experience mental health problems during the perinatal period. Maternal stress and distress during pregnancy and postnatally can impact infant developmental outcomes, including gross motor development. Cortisol, a steroid hormoneand output of the HPA axis, is often attributed as the mediating mechanisms between maternal perceived stress and infant outcomes. However, there is a lack of evidence supporting cortisol as a mediator between maternal subjective stress and infant gross motor development. The current study sought to explore potential behavioral factors that might mediate the relationship between maternal perinatal stress, including perceived stress and cortisol, and infant gross motor outcomes. It was hypothesized that maternal-infant physical touch at 6 months postnatally would mediate the relationship between maternal perinatal stress indices and infant gross motor outcomes at 14 months. Additionally, we examined the associations among maternal stress indices across the perinatal period. Participants were pregnant females recruited from a community sample in their third trimester (33-37 weeks gestation). Mothers returned to the lab with their infants at 6 months and 14 months for a behavioral observation session. Maternal-infant touch behavior was coded during a brief free-play session. Data was analyzed using a series of Pearson’s correlations, simple linear regression, and Hayes’ PROCESS macro for mediation analyses. Analyses revealed that maternal-infant touch did not significantly mediate the relationship between maternal perinatal stress indices and infant gross motor outcomes. Notably, we did find that maternal-infant touch negatively predicted infant gross motor outcomes, such that higher frequency of maternal-infant touch resulted in decreased infant gross
xvimotor scores. These findings suggest that restrictive maternal touch captured during free-play session might influence infant motor development, independently of maternal mental health status. Key Words: subjective stress, AUC, CAR, motor development, maternal-infant reciprocity |