This randomized controlled trial aims to evaluate the effect of nesting during the first intramuscular injection on pain, stress level, physiological parameters, settling time, and breastfeeding success in healthy term newborns delivered by cesarean section. A total of 112 newborns will be randomly assigned in a 1:1 ratio to either a nesting intervention group or a routine care control group. Newborns in the intervention group will receive nesting until the first intramuscular injection, whereas those in the control group will receive routine neonatal care. Pain, stress level, physiological parameters, settling time, and breastfeeding success will be evaluated using validated assessment tools. The findings are expected to provide evidence regarding the effectiveness of nesting as a simple, safe, and non-pharmacological intervention for reducing procedural pain and stress in newborns while supporting breastfeeding success.