Background: Intra-abdominal adhesions are frequent side effects of surgery, associated with risks of serious complications such as abdominal pain, infertility, and small bowel obstruction. This study investigated a new autologous blood-based approach to adhesion prophylaxis. Materials and method: Two autologous blood-derived patches (whole-blood-derived, n = 20, and plasma-derived, n = 20) were evaluated as anti-adhesives. The patches were tested in a rat uterine horn damage model. We simulated an intraabdominal surgery by cauterizing and suturing the uterine horns and created an opposing damage by denuding a part of the abdominal wall. Each rat served as its own control with one treated uterine horn and one untreated. After 14 d of post-surgical recovery, the adhesions were assessed and graded macroscopically and microscopically. Statistical analyses were performed with Wilcoxon signed rank and Mann–Whitney U tests. Results: Both whole-blood and plasma-derived patches resulted in significantly less macroscopic adhesions than were found in untreated uterine horns (P = 0.001 and P = 0.002, respectively). Unpaired analysis found no significant differences between the whole-blood and plasma-derived patch outcomes in this study design. Histopathological evaluation of inflammation and fibrosis did not reveal significant differences between the patches and their matched controls. Conclusions: The autologous blood-derived patches reduced macroscopic adhesion formation significantly compared with no treatment. There were no adverse events and no histological differences between treatment and control, suggesting that the treatments were feasible and safe. In summary, this study confirms the potential of autologous anti-adhesives for the use in intraabdominal surgery.