Subgroup analysis indicated that the intra-uterine infusion of G-CSF was notably effective in diminishing the miscarriage rate (RR = 0.35, 95% CI (0.18, 0.68), P = 0.002), while subcutaneous administration did not exhibit a significant impact (RR = 0.55, 95% CI (0.26, 1.20), P = 0.13). Here, CSF3 is linked to spontaneous abortion.