A prosthesis is provided that is advantageously used to fill a soft tissue or muscle defect, such as an inquinal or femoral hernia. In a first aspect of the invention, multiple layers of a flexible, mesh material are attach together at a finite number of joins. A tab is placed at the geometric center of one of the mesh layers to facilitate insertion of the mesh into the defect. The tab also creates a blunt tip that reduces irritation and discomfort to the patient. In a second aspect of the invention, a prosthesis is provided that includes a barrier layer between two or more layers of flexible, mesh material to prevent adhesion of the device to the tissue. All layers are attached together by a finite number of joins. A tab is placed at the geometric center of one of the mesh layers to facilitate insertion of the mesh into the defect. The prostheses of the invention are self-forming in that they change from a two dimensional configuration to a three dimensional configuration upon insertion of the device into the defect.