Introduction: Strategies for optimal prophylaxis in pregnant women with a history of venous thromboembolism (VTE) are not currently based on high-quality evidence. Both Thromboembolism and anticoagulation treatment account for significant maternal morbidity and mortality. This study examined patients with thromboembolism associated with pregnancy and evaluated the efficiency of Aspirin against anticoagulation in secondary prophylaxis during pregnancy.
Methods: A retrospective analysis was conducted on 106 consecutive episodes of pregnancy in 89 women, with previous venous thromboembolic events. In 72 episodes, patients received 150 mg/day of Aspirin only. In the other 34 episodes, patients received prophylactic anticoagulation in the form of low molecular weight heparin (LMWH). Patients were given the secondary prophylaxis medication throughout the whole period of pregnancy and followed up for 6 weeks postpartum.
Results: The patient's mean age was 25 (±SD 3.7) years. Re-thrombosis developed in 13% of the Aspirin-only group versus 20 % in the anti-coagulation group (P = 0.025). The shorter the duration between the last episode of VTE and the new conception, the higher the re-thrombosis rate (p value=0.0001). The rate of re-thrombosis was higher in patients with previous unprovoked VTE compared to those with provoked events (20.8% Vs. 12.2% p value=0.049) irrespective of the anticoagulation protocol.
Conclusions: Aspirin is not inferior to pLMWH in 2ry prevention of VTE in pregnant females. Implementation of anticoagulation should be tailored according to risk factors rather than pregnancy. The longer the gap between VTE and subsequent pregnancy the lower the re-thrombosis rate. This emphasizes the importance of gestational regulation following VTE.