Can Polycythemia Vera Cause Heavy Uterine Bleeding?
Yes, Polycythemia Vera (PV) can cause heavy uterine bleeding in females of reproductive age, though this is not the most common manifestation of the disease. The bleeding risk in PV stems from multiple mechanisms including acquired platelet dysfunction, particularly when platelet counts are extremely elevated (≥1000 × 10⁹/L), which can lead to acquired von Willebrand disease 1.
Hemorrhagic Complications in PV
Bleeding events occur in approximately 2-4.5% of women with PV during pregnancy and the postpartum period 2. The evidence from multiple pregnancy cohorts demonstrates:
- In the European LeukemiaNet series of 121 pregnancies in women with PV, the incidence of bleeding events was higher in pregnancies after PV diagnosis compared to before diagnosis 2
- Major bleeding complications occurred in 2-25% of pregnancies across different series, with postpartum hemorrhage being specifically documented 2
- One UK study reported bleeding events in patients with platelet counts >1500 × 10⁹/L as a high-risk feature requiring intervention 2
Mechanisms of Bleeding in PV
The pathophysiology involves several factors 2, 1:
- Acquired von Willebrand disease develops with extreme thrombocytosis (platelet count ≥1000 × 10⁹/L), causing abnormal platelet function and bleeding tendency 1
- Platelet dysfunction occurs despite elevated platelet counts, with abnormal platelet aggregation and impaired interaction with coagulation factors 2
- Hyperviscosity from elevated hematocrit can paradoxically contribute to both thrombotic and hemorrhagic complications 2
Clinical Context and Risk Factors
High-risk features for hemorrhagic complications include 2:
- Prior hemorrhagic events
- Platelet count >1500 × 10⁹/L
- Extreme thrombocytosis without adequate cytoreductive therapy
- Pregnancy and postpartum period (when bleeding risk is amplified)
Important Clinical Caveats
The dual thrombotic-hemorrhagic paradox in PV requires careful management 3, 4, 5, 1:
- While thrombosis is the predominant vascular complication (occurring in 16% arterial and 7% venous events at or before diagnosis), bleeding remains a significant concern 1
- Aspirin therapy, recommended for all PV patients to reduce thrombotic risk, must be carefully weighed against bleeding risk in patients with extreme thrombocytosis 5, 1
- In pregnant women with PV, the 17% maternal complication rate includes both thrombosis and hemorrhage, with postpartum hemorrhage specifically documented 2
For women of reproductive age presenting with heavy uterine bleeding and elevated blood counts, PV should be considered in the differential diagnosis, particularly if accompanied by thrombocytosis, leukocytosis, or splenomegaly 1. Testing for the JAK2V617F mutation (present in >95% of PV cases) is essential for diagnosis 4, 1.