Objective <p>To evaluate the efficacy of an online nursing consultation on the Red Sinapsis (RS) Internet platform in increasing maternal self-efficacy and exclusive breastfeeding rates during the first month postpartum.</p> Methods <p>This study employed a controlled, randomised experimental design with two groups. Ninety women who had undergone caesarean sections were randomly assigned to either an intervention group (n = 45) or a control group (n = 45). The intervention group received follow-up care from a breastfeeding expert nurse on the RS online platform, while the control group received standard follow-up care from a midwife or primary care nurse.</p> <p>Breastfeeding success was measured using the LATCH scale at 15&#xa0;days postpartum and the BSES-SF scale at 30&#xa0;days postpartum. For comparative analysis between study groups, Fisher’s exact test or the chi-squared test was used, depending on the contingency table dimensions. Missing values were not imputed. P-values below the 0.05 threshold were considered statistically significant.</p> Results <p>A total of 84% of the intervention group showed greater confidence in providing breast milk to their children, compared to 44% of the control group (p &lt; 0.001). The intervention group also achieved better outcomes in terms of believing that breastfeeding alone is sufficient to nourish their baby, with 82% expressing confidence, compared to 59% in the control group (<i>p</i> = 0.041).</p> Conclusions <p>Online nursing follow-up during the immediate postpartum period improves maternal confidence in breastfeeding, promoting its initiation and establishment during the first month postpartum.</p>