Cathodoluminescence in the scanning electron microscope and roentgenogram diffraction studies were applied to the analysis of two different medical materials used in cervical cerclage, the treatment of cervical incompetence. Braided polyester tape or Gore-Tex was used as suture material and was analyzed both before and after use in cerclage of the cervix. Results of SEM and X-ray diffraction studies showed distinct differences between the two materials, with the Gore-Tex demonstrating a superior morphological integrity and a decreased likelihood of phagocyte adhesion. These results correlated well with the clinical observations, which also showed Gore-Tex to be a superior medical material.