Intrauterine Infusion and Sub-endometrial Injection of Autologous Platelet-Rich Plasma for Thin Endometrium: A Systematic Review and Single-Arm Meta-Analysis

Objective: To evaluate the efficacy and safety of intrauterine infusion or sub-endometrial injection of autologous platelet-rich plasma (PRP) on endometrial thickness and pregnancy outcomes in women with thin endometrium undergoing frozen–thawed embryo transfer (FET) cycles.

Materials and Methods: A comprehensive search was conducted across PubMed, Embase, Web of Science, and the Cochrane Library. Studies utilizing PRP for thin endometrium in FET cycles were selected based on PRISMA guidelines. The methodological quality was assessed using the MINORS tool. A single-arm meta-analysis was performed using R software to calculate pooled mean differences (MD) for endometrial thickness (EMT) and pooled rates for pregnancy outcomes.

Results: Fourteen studies comprising 523 patients were included. The meta-analysis demonstrated that PRP treatment significantly increased EMT (MD = 1.61 mm, 95% CI: 1.21–2.01, p < 0.05). Following PRP intervention, the pooled clinical pregnancy rate was 41.5% (95% CI: 29.6%–53.9%). The ongoing pregnancy rate was 27.3% (95% CI: 19.7%–35.0%), implantation rate was 22.9% (95% CI: 8.5%–37.2%), and miscarriage rate was 5.3% (95% CI: 2.3%–8.2%). Subgroup analyses indicated that study design and administration route contributed to heterogeneity.

Conclusion: Autologous PRP therapy appears to be a safe and effective strategy for improving endometrial receptivity and reproductive outcomes in patients with thin endometrium. While current single-arm data provide a promising clinical benchmark, standardized large-scale randomized controlled trials are required to confirm these findings.