<qa>  How many patients were included in the PRP-AH injection sessions?The aim of this prospective study is to assess the efficacy of autologous Platelet Rich Plasma combined with Hyaluronic Acid prepared with RegenKit-BCT HA Cellular Matrix on skin rejuvenation. Thirty-one patients were included and received three PRP-AH injection sessions 4 weeks apart into the cheeks. The outcomes were assessed at baseline, 1, 3 and 6 months after the last injection session. Safety was assessed by reported adverse event analysis. 