Abstract: Objective: To investigate the clinical effect of intrauterine perfusion of the granulocyte colony-stimulating factor (G-CSF) combined with low molecular weight heparin (LMWH) on the clinical outcomes of freeze-thaw embryo transfer (FET) in those patients with thin endometrium. Methods: A total of 175 patients with thin endometrium who received FET in the First Hospital of Shanxi Medical University from June 2018 to October 2019 were selected and divided into 3 groups. Group A: 63 patients only received hormone replacement therapy as the control group. Group B: 52 patients received hormone replacement therapy and intrauterine G-CSF perfusion. Group C: 60 patients received hormone replacement therapy and intrauterine G-CSF perfusion and subcutaneous injection of LMWH. Endometrial thickness, endometrial blood flow resistance index (RI), pulse index (PI), cycle cancellation rate, embryo implantation rate, clinical pregnancy rate, early abortion rate, ectopic pregnancy rate and other indicators of the three groups were compared. Results: On the endometrial conversion day, of endometrial thickness, type Ⅱ+Ⅲ blood flow type rate in the group B and C were significantly increased when compared with group A, while RI and PI in the group B and C were significantly lower (all P＜0.05). The embryo implantation rate, clinical pregnancy rate and cycle cancellation rate in the group B and C were significantly reduced when compared with group A (P＜0.05), and there were no significant differences between the group B and C (P＞0.05). The early abortion rate in the group C was significantly lower than that in the group B (P＜0.05). Conclusions: Intrauterine perfusion of G-CSF during the FET cycle can significantly improve the endometrial thickness of patients with thin endometrium, the blood flow of endometrium, the embryo implantation rate and clinical pregnancy rate. The combined LMWH injection can reduce the early abortion rate.

Key words: Endometrium;, Granulocyte colony-stimulating factor;, Heparin, low-molecular-weight, Embryo transfer;, Administration, topical, Hemodynamics, Pregnancy rate