Preclinical phase of polycythemia vera in pregnancy

Myeloproliferative disorders in pregnancy

This article reviews pregnancy outcome in women diagnosed with a myeloproliferative neoplasm (MPN), and discusses possible risk markers and the pathogenesis of poor pregnancy outcome. An outline of the key factors regarding the diagnosis and management of MPN in women of reproductive potential is followed by a description of the authors' management strategy for standard and high-risk pregnancy in MPN patients.

Polycythemia vera and pregnancy: experience of four pregnancies in a single patient

INTRODUCTION

The association of polycythemia vera (PV) and pregnancy is rare. The estimated incidence ranges from 0.04 per 100,000 in women aged 20-34 years to 0.25 per 100,000 in those aged 35-39 years. The management of pregnant patient with PV may be problematic; less than 50 pregnancies have been reported so far in PV.

MATERIAL AND METHODS

We hereby describe four pregnancies in a woman where PV was diagnosed in the fourth pregnancy. Aspirin and phlebotomy were used to maintain cell count in normal range and to avoid thrombotic complications.

CONCLUSION

Pregnancy in PV appears to be associated with significantly better outcome with tailor-made management for achieving good hematocrit control, low-dose aspirin and good maternal and fetal surveillance.

Pregnancy and its management in the Philadelphia negative myeloproliferative diseases

The myeloproliferative diseases (MPDs) present several therapeutic challenges in patients of childbearing potential. The most extensive literature exists for patients with essential thrombocythaemia, with over 200 pregnancies reported in retrospective case series. Yet there is conflicting data in relation to predicting pregnancy outcome and optimal management strategy. Pregnancy is less frequently reported for polycythaemia vera and myelofibrosis. There is a need for collaboration to further our knowledge in this field. Here, the literature is reviewed in detail and experience of different therapeutic strategies in pregnancy discussed. There is increasing understanding about the pathogenesis of placental dysfunction in inherited thrombophilia and antiphospholipid antibody syndrome pregnancy outcomes in these conditions parallel those reported for MPDs. Furthermore several large studies have influenced pregnancy management in these conditions and, whilst not directly applicable to MPDs, this data have potential to inform treatment protocols. This data are reviewed and a personal management strategy for pregnancy in MPD proposed.

[Polycythemia vera and pregnancy: difficulties for diagnosis and treatment]

Polycythemia vera is a myeloproliferative syndrome. This clonal disorder involves a pluripotent stem cell capable of differentiating into red blood cells, granulocytes, and platelets. Polycythemia vera is characterized by the overproduction of mature red blood cells in the bone marrow. Myeloid and megakaryocytic elements are also often increased. Polycythemia vera (PV) is rarely associated with pregnancy. About 20 cases have been reported. Prognosis of PV is not influenced by pregnancy. Conversely, pregnancy outcome is poor, due to the occurrence of gestational hypertension, stillbirth and induced prematurity. During pregnancy, clinical management needs to be close including a collaborative approach between obstetricians, hematologists and anesthesists. The risk of poor outcome may be reduced by the association of antiaggregant and anticoagulant therapy. Phlebotomy can be provided in order to maintain hemoglobin level under 42%.

[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.