[Polycythemia vera and pregnancy].

Polycythemia vera is a rare chronic myeloproliferative disease. Its exceptional association with pregnancy can lead to severe complications. Antithrombotic treatment could prevent such adverse outcome. A patient with two previous pregnancies complicated by preeclampsia, was treated by hydroxyurea for polycythemia vera. She started a new unexpected gestation without this myelosuppressive treatment and the pregnancy was conducted uneventfully with low molecular weight heparin and low dose aspirin. Thrombotic complications required the reintroduction of hydroxyurea. Diagnosis of polycythemia vera during pregnancy is a very difficult task due to physiologic changes occurring during gestation. Adverse outcome including severe vascular complications can be a preclinical phase of the disease. An adequate therapy could prevent these complications.