Evaluating the efficacy of granulocyte-macrophage colony-stimulating factor in improving implantation rates in frozen embryo transfer cycles: a blind randomized-controlled study

Implantation failure in assisted reproductive technologies (ART) remains a challenge. Granulocyte-macrophage colony-stimulating factor (GM-CSF) may enhance embryo implantation, but its efficacy needs more investigation. This study aimed to assess if adding GM-CSF to thawed embryo culture could improve implantation rates in frozen embryo transfer cycles.

One hundred rats were randomly assigned to GM-CSF or control groups at Avicenna Infertility Clinic, Tehran. Control group had standard embryo culture; GM-CSF group had embryos cultured in Embryogen® with GM-CSF. Pregnancy outcomes were assessed via serum β-HCG levels post frozen embryo transfer (FET) and ultrasonography at gestational week seven.

No significant difference in blastocyst formation rates was found between groups. Positive beta-HCG levels were 36% in control and 40% in GM-CSF groups. Gestational sacs were detected in 36% of control and 34% of GM-CSF group during weeks 5-6. Clinical pregnancy rates were 32% in control and 30% in GM-CSF groups.

GM-CSF in embryo culture of thawed embryos shows no significant impact on blastocyst formation or pregnancy outcomes. However, interventions like these may enhance fertility treatments, warranting larger-scale clinical trials for further exploration.