What this Trial Is About

Preterm infants are exposed to multiple stressors each day, posing a risk of toxic stress that can impact their developing brains during a critical period of sensitivity. Elevated levels of the stress hormone cortisol can impede neuronal connectivity and communication, thereby increasing the likelihood of cognitive impairment and behavioural problems. Synchronized social-emotional mother-infant interaction holds promise in buffering stress reactivity and mitigating long-term stress effects. Our previous research has shown that preterm infants exhibit higher baseline saliva cortisol levels than full-term infants, along with blunted cortisol reactivity to stressors, irregular cortisol circadian rhythms, and delayed cortisol co-regulation between mother and infant. Another potential stress marker is saliva alpha-amylase (α-amylase), which has garnered increasing interest in adult research. However, there remains a significant gap in the literature concerning saliva α-amylase as a stress marker in preterm infants, warranting further investigation. The overall aim is to study development and relationships between three systems of parent-infant synchrony in preterm infants and their parents and elucidate potential confounding factors for a synchronous correlation. This will be done in relation to standardised care procedures commonly performed in the neonatal intensive care unit. This observational study will involve 35 families undergoing three video-recorded procedures in the NICU. Saliva will be collected from infants and both parents before and after each procedure so we can analyse co-regulation of cortisol and alpha-amylase. Parent-infant interaction will be analysed from the videos using validated scales. This study will be the first to document biological co-regulation and social-emotional parent-infant interaction simultaneously involving preterm infants and both parents in the NICU setting. Such insights are pivotal for the future design and implementation of tailored nursing interventions aimed at early stress mitigation, thereby reducing the risk of stress-related consequences.

Co-regulation and Interaction in the NICU