RESUMO
Uterine myomas are common but erythrocytosis caused by these is rarely seen. We report a case that illustrates the conjunction of various aetiological factors required for this clinical entity to evolve. A voluminous, retroperitoneally located and focally degenerated myoma was associated with severe secondary erythrocytosis (haematocrit: 65.5%) which resolved after hysterectomy. It has been demonstrated previously that myomatous tissue is the source of excessive production of erythropoietin. Local tissue hypoxia, which is more prone to develop in a pedunculated myoma, stimulates the process. Other prerequisites are a very large size of the myoma and the absence of menometrorrhagia of a severity such as to cause a depletion in iron reserves.