Background: Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) is a cytokine that plays a crucial role in immune regulation and influencing embryo development by enhancing cellular communication and growth. In the context of assisted reproductive technologies like Intracytoplasmic Sperm Injection (ICSI), optimizing culture conditions is essential to improve embryo quality and increase pregnancy success rates. Recent studies have suggested that GM-CSF supplementation in culture media may offer benefits by promoting embryo viability and developmental potential. Objective: To explore the impact of GM-CSF-enriched culture media on ICSI outcomes, including embryo cleavage, blastocyst formation, and pregnancy rates. Methods: A randomized, double-blind clinical trial was conducted involving 100 women undergoing assisted reproductive technology over two years (January 2022 - January 2024). Participants were divided into two groups: a control group receiving standard culture media and a treatment group receiving GM-CSF-supplemented culture media. ICSI outcomes were compared between the two groups. Results: Significant differences were observed in the number of cleaved oocytes, top-cleaved oocytes, and blastocysts between the control and GM-CSF-supplemented groups (p=0.001, p=0.03, and p=0.003, respectively). The GM-CSF group demonstrated higher cleavage rates (p<0.04), top cleavage rates (p=0.02), and blastocyst formation rates (p=0.007) compared to the control group. Furthermore, the GM-CSF group had a significantly higher number of transferred embryos (p=0.037) and pregnancy rates (p=0.04). Conclusions: GM-CSF supplementation in culture media significantly improves key developmental and clinical outcomes in ICSI, including cleavage rates, top cleavage rates, blastocyst formation, and pregnancy rates, compared to standard culture media.