<p>This study aimed to examine the effects of early skin-to-skin contact (SSC) on neonatal stress as the primary outcome and—together with early initiation of breastfeeding—on fifth-day total serum bilirubin (TSB) levels as a secondary outcome. Mother–newborn dyads were randomly assigned to the control (<i>n</i> = 30) or SSC group (<i>n</i> = 30). Neonatal stress was assessed immediately after birth, under a radiant warmer, and during intramuscular (IM) vitamin K injection using the Newborn Stress Scale (NSS); the SSC group was evaluated five minutes after SSC initiation. TSB levels were measured on the fifth day post-discharge. NSS scores did not differ significantly between groups immediately after birth or under a radiant warmer (<i>p</i> &gt; 0.05). Five minutes after SSC began, the NSS score was 0.00 [1.00]. However, within the intervention group, NSS scores significantly decreased five minutes after starting SSC compared with initially after birth. During injection, NSS scores were significantly lower in the SSC group than in the control group (<i>p</i> &lt; 0.05). Fifth-day TSB levels did not significantly differ between the groups (<i>p</i> &gt; 0.05). Early SSC was associated with lower neonatal stress during IM vitamin K injection and with reduced stress scores after SSC initiation. However, it does not significantly affect early bilirubin levels.</p>