Platelet-Rich Plasma for Androgenetic Alopecia: A Meta-Analysis

Abstract

Introduction: Platelet-rich plasma (PRP) has gained popularity for hair restoration. This meta-analysis quantifies its efficacy in male and female androgenetic alopecia (AGA). Methods: Fifteen RCTs (n=672) identified from MEDLINE, Embase, and CENTRAL (2015–2024). Primary outcomes: change in hair density (hairs/cm²) and hair diameter after 3–6 months. Results: PRP significantly increased hair density by 18.4 hairs/cm² (95% CI: 12.7–24.1) and hair diameter by 12.3 μm (95% CI: 8.9–15.7) compared to placebo. Efficacy was greater with three monthly sessions than single injection. No serious adverse events reported. Discussion: Growth factors (PDGF, VEGF, FGF) likely prolong anagen phase. However, preparation protocols varied widely (centrifugation speed, activation method), introducing potential bias. Conclusions: PRP is a safe, moderately effective treatment for AGA. Standardized preparation guidelines are urgently needed.