Touch facilitates newborns' self-regulation: Systematic review of multidimensional arousal outcomes.

During the first month of life, exchanges between newborns and caregivers focus on helping babies regulate their physiological and behavioural states. Touch and bodily contact play a special role in facilitating arousal regulation and are often used to promote bonding, support at-risk babies, and manage pain. Here, we systematically review the extant evidence on the effects of touch interventions for newborns, specifically focusing on self-regulation and arousal as outcome measures. Seventy-two experimental studies met our inclusion criteria, comparing touch and control groups or within-subject conditions across a variety of physiological and behavioural outcomes. The types of touch interventions employed include skin-to-skin care, Kangaroo Care, massage therapy, Gentle Human Touch, and Yakson. Outcome measures include heart rate and heart rate variability, blood oxygenation and respiration rate, body temperature regulation, cortisol levels, and behavioural states (e.g., sleep and crying patterns). Most studies implemented touch interventions on premature babies and measured outcomes within the first month of life. Only a minority monitored the long-term effects of interventions or explored facilitating factors such as multisensory aspects, caregiver satisfaction, and sensitivity to the baby's signals. Overall, the findings consistently show the benefits of touch in promoting the immediate self-regulation skills of newborns, particularly supporting the use of tactile interventions for premature babies and neonatal pain management in clinical contexts. Future research should further investigate the long-term, cascading effects of touch interventions on broader dimensions of child development and the child-caregiver dyad's well-being as a whole.