The effect of self-reinforced polyglycolide (SR-PGA) absorbable membranes on metaphyseal bone was studied in eighty-seven rats. SR-PGA membranes, 0.15 mm thick, were implanted on the femoral metaphyseal bone: on the periosteum, and directly on bone after periosteal stripping. In a control group, only periosteal stripping was performed. The rats were killed after 1, 3, 6, 12 and 24 weeks. Fibrous tissue formation around the implant, periosteal thickening and new bone formation occurred more extensively when SR-PGA membranes were implanted directly on bone after periosteal stripping. Fibrous tissue invaded the membranes. At twenty-four weeks, few fibre remnants were found embedded in a rim of fibrous tissue. No locally adverse reactions were recorded. Polyglycolide (PGA) appeared to have a positive inductive effect on new bone formation.