The banning of synthetic transvaginal mesh for treating Pelvic Organ Prolapse (POP) in Australia, UK, USA and NZ has left millions of women with few effective treatment options. We are developing a new mesh to deliver endometrial MSC (eMSC) to improve mesh biocompatibility and restore strength to prolapsed vaginal tissue. Here we evaluated our knitted polyamide (PA) mesh in a novel ovine multiparous, transvaginal implantation model, matching ewes for the degree of POP. Gelatin-coated PA mesh stabilised with 0.5% glutaraldehyde (PA/G) used either alone or seeded with autologous ovine eMSC (eMSC/PA/G) resulted in poor tissue integration and 42% mesh exposure in this model. In contrast, a two-step insertion protocol, whereby uncoated PA mesh was inserted transvaginally followed by application of autologous eMSC in a gelatin hydrogel onto the mesh and crosslinked with blue light in situ (PA+eMSC/G), integrated with no mesh exposure. The autologous ovine eMSC persisted 30 days in vivo influencing the host inflammatory, extracellular matrix remodelling, neovascularisation, fibrotic and biomechanical responses, but not mesh integration, indicating the value of an autologous approach. The stiff PA/G constructs provoked greater myofibroblast and inflammatory responses in the vaginal wall, disrupted the muscularis layer and reduced elastin fibre content compared to PA+eMSC/G constructs. This study provides new biomaterials for POP research and an improved animal model, but also highlights the complexity of the problem of POP therapy. However, it identified the superiority of a two-step protocol for implanting synthetic mesh in cellular compatible composite constructs and simpler surgical application, providing additional translational value.