['The aim of this study was to investigate a possible relationship between fetal cell microchimerism and lichen sclerosus of the vulva. We searched for the presence of male cells and DNA in vulval tissue samples.', 'Paraffin-embedded skin biopsy samples from 15 women affected with vulval lichen sclerosus who gave birth to at least one son were analyzed for the presence of microchimeric male cells using fluorescence in situ hybridization (FISH) and fluorescent PCR. We included three lichen sclerosus samples originating from women without male offspring, six vulval specimens without pathological finding originating from autopsies and seven male gingival specimens as controls.', 'Nucleated cells containing Y-chromosome specific sequences were neither detected at any site of the lesions nor in normal vulval specimens by using FISH. These results were confirmed by the use of PCR amplification demonstrating only DNA sequences specific for the X chromosome. No female microchimerism was detected in the male gingival samples.'] Is fetal microchimerism involved in the pathogenesis of lichen sclerosus of the vulva?