The invention relates to prostheses having a multi-layered sheet structure comprising at least two continuous polymer film layers. Also disclosed are methods of manufacturing the prostheses, as well as methods of treating a patient by implanting them into a patient. The prostheses are used in hernia repair, the repair of anatomical defects of the abdominal wall, diaphragm and chest wall, correction of defects in- the genitourinary system, and repair of traumatically damaged organs such as the spleen, liver or kidney.
