Postcaesarean section uterovesical fistula lined by persistent intermediate trophoblast.

We report a unique case of a postcaesarean section uterovesical fistula lined by intermediate trophoblast. The patient, a 42-year-old woman, presented with cyclical haematuria, and she had had a lower segment caesarean section 1 year previously. She was found to have uterovesical fistula, which was excised. On microscopic examination the fistula tract was lined by intermediate trophoblast characterised by cells with abundant eosinophilic cytoplasm, occasional multiclefted nuclei, and cytoplasmic immunoreactivity for epithelial cytokeratins and human placental lactogen. This finding has not, to our knowledge, been previously described and indicates that the survival of third trimester intermediate trophoblast is independent of pregnancy.