Intrauterine platelet-rich plasma infusion with hormone replacement therapy improves menstrual and pregnancy outcomes in thin endometrium patients undergoing frozen-thawed embryo transfer

Objective To evaluate the effect of intrauterine infusion of platelet-rich plasma (PRP) on luteal support and pregnancy outcomes in patients with thin endometrium undergoing frozen-thawed embryo transfer (FET).Methods A total of 160 patients with thin endometrium undergoing FET from March 2023 to March 2024 were assigned to the observation group (PRP infusion, n = 80) or the control group (conventional treatment, n = 80). All patients underwent hormone replacement therapy cycles,with PRP infused on days 9, 11, and 13 in the observation group. Outcomes included endometrial thickness, uterine hemodynamic parameters (PI, RI), PBAC-assessed menstrual volume, pregnancy outcomes, and embryology-related variables. Logistic regression identified independent factors associated with clinical pregnancy. Adverse events were also recorded.Results Post-treatment, the observation group had greater endometrial thickness and lower PI and RI values than the control group. PBAC scores, clinical pregnancy rate (36.25% vs. 21.25%), and live birth rate (25.00% vs. 12.50%) were significantly higher, while preterm birth rate did not differ. Embryo transfer–related variables were comparable between groups. Multivariate analysis identified PRP infusion and endometrial thickness at transfer as independent protective factors for clinical pregnancy, whereas advanced age was an unfavorable factor. No obvious adverse events occurred.Conclusion PRP infusion enhances endometrial receptivity by improving thickness and blood perfusion, thereby increasing pregnancy and live birth rates in thin endometrium patients undergoing FET. It is safe and may be used as an effective adjunct in endometrial preparation.