RESUMO
We present an ultrastructural study of the utilization of human amniotic membrane in the treatment of congenital abscence of the vagina in 10 patients. All patients were surgically treated with application of an amniotic membrane graft using the modifified McIndoe and Bannister technique. Sixty days after surgery, samples of the vaginal neoepithelium were collected for transmission electron microscopy analysis. The ultrastructural findings consisted of a lining of mature squamous epithelium indicating the occurrence of metaplasia of the amniotic epithelium into the vaginal epithelium. The cells were arranged in layers as in the normal vaginal epithelium, i.e., superficial, intermediate and deep layers. There were desmosomes and cytoplasmic intermediate cytokeratin filaments, as well as some remnant features of the previous amniotic epithelium. These findings suggest that human amniotic membrane is able to complete metaplasia into squamous cells but the mechanism of this cellular transformation is unknown.