Effect of intrauterine perfusion of granular leukocyte-colony stimulating factor on the outcome of frozen embryo transfer

BACKGROUND: Treatment of thin endometrium with granular leukocyte-colony stimulating factor (G-CSF) remains controversial. AIM: To investigate the effect of G-CSF on the outcome of frozen embryo transfer in patients with thin endometrium. METHODS: A retrospective propensity score matching (PSM) study was performed to assess patients administered frozen embryo transfer at the Reproductive Medicine Center of the Affiliated Drum Tower Hospital of Nanjing University Medical School, in 2012-2018. The patients were divided into G-CSF intrauterine perfusion (G-CSF) and non-G-CSF groups, and clinical pregnancy, implantation, ectopic pregnancy, and early abortion rates between the two groups were compared. RESULTS: Before PSM, 372 cycles were enrolled, including 242 and 130 cycles in the G-CSF and non-G-CSF groups, respectively. Age (34.23 ± 5.76 vs 32.99 ± 5.59 years; P = 0.047) and the blastula/cleavage stage embryo ratio (0.68 vs 0.37; P = 0.011) were significantly elevated in the G-CSF group compared with the non-G-CSF group; however, clinical pregnancy (46.28% vs 51.54%; P = 0.371) and embryo implantation (35.21% vs 35.65%; P = 0.910) rates were similar in both groups. After PSM by age and blastula/cleavage stage embryo ratio, 244 cycles were included (122 cases each in the G-CSF and non-G-CSF groups). The clinical pregnancy (50.82 % vs 48.36%; P = 0.701) and embryo implantation (37.38% vs 34.11%; P = 0.480) remained similar in both groups. CONCLUSION: Intrauterine infusion of G-CSF does not improve the clinical outcome of frozen embryo transfer in patients with thin endometrium.