Intraovarian injection of autologous platelet-rich plasma combined with peripheral blood mononuclear cells improves ovarian function in advanced-age women with diminished ovarian reserve: a clinical retrospective cohort and single-cell transcriptomic analysis

To perform a preliminary, hypothesis-generating evaluation of the association between intraovarian injection of platelet-rich plasma (PRP) combined with peripheral blood mononuclear cells (PBMCs) and ovarian response parameters in advanced-age women with diminished ovarian reserve (DOR), and to explore potential underlying mechanisms using a complementary animal model. A retrospective, non-randomized cohort analysis was conducted on 122 advanced-age DOR patients undergoing IVF-ET. Group allocation was based on patient preference and financial considerations following comprehensive counseling. Patients were accordingly categorized into a blank control group (n = 45), a PRP group (n = 47), or a PRP + PBMCs group (n = 30). Key confounding factors were adjusted for using Inverse Probability of Treatment Weighting (IPTW). In parallel, a small-scale (n = 5 per group) animal study using a 13-month-old DOR rat model was performed to generate mechanistic hypotheses. Ovaries were harvested 10 days post-intraovarian injection for single-cell RNA sequencing (scRNA-seq). Primary hypothesis-generating outcomes were changes in AMH and AFC; oocyte retrieval outcomes were pre-specified secondary endpoints. In this observational analysis, after statistical adjustment for key confounders using IPTW, the PRP + PBMCs group showed a nominally higher mean number of oocytes retrieved (adjusted mean difference: 0.90, 95% CI: 0.25 to 1.55, p = 0.007) and metaphase II (MII) oocytes (adjusted mean difference: 0.88, 95% CI: 0.20 to 1.56, p = 0.014) compared to the PRP alone group. These statistically significant findings in adjusted analyses should be interpreted as exploratory within the context of this non-randomized study. For the pre-specified primary hypothesis-generating outcomes, changes in serum AMH levels and antral follicle count (AFC) from baseline showed positive trends but did not reach statistical significance in the IPTW-adjusted comparison. No serious adverse events were reported. In the complementary exploratory animal study, rats receiving PRP + PBMCs showed improved follicle counts and hormone levels compared to controls. Single-cell transcriptomic analysis suggested potential alterations in intercellular communication among granulosa cells and activation of pathways related to protein synthesis and energy metabolism. In this retrospective, hypothesis-generating study, an association was observed between intraovarian PRP + PBMCs injection and increased oocyte yield in adjusted analyses. The exploratory mechanistic data suggest that this potential effect may involve metabolic and immunomodulatory reprogramming of the ovarian microenvironment, a hypothesis that requires direct validation. Importantly, this study was not powered to assess pregnancy or live birth outcomes. Collectively, these preliminary findings do not establish clinical efficacy but serve to highlight the need for and inform a prospective, randomized controlled trial to definitively evaluate this combined approach.