PB0468 - Pregnancy Induced Thrombosis: a clinical study.

Background: In developed countries, venous thromboembolic events (VTE) present a significant risk during pregnancy and postpartum, with a 5-fold and a 20-fold higher risk respectively, compared to non-pregnant women.
Multifactorial pathogenesis involves elevated coagulation factors, reduced fibrinolysis and physical changes related to fetal position and delivery-related vascular trauma. Lacking an individual risk biomarker, developing an efficient tool for continuous pregnancy monitoring is crucial.

Aims: This study therefore aims to assess thrombotic markers and their evolution throughout pregnancy to optimize thrombotic risk management and patient-oriented therapeutic interventions.

Methods: This study is a single-centered prospective study willing to recruit 150 pregnant women over 15 months. The study aligns with Centre Hospitalier Régional de Huy’s standard care time-points (7 weeks, 3-, 6-, 9 months, delivery Day+2, and 6 months post-partum). This study received ethical approval (N°035-10/2022) and follows the Declaration of Helsinki.
Demographic characteristics and common thrombotic risk factors will be tabulated. Besides usual clinical parameters, global coagulation tests such as thrombin generation test (TGT), activated protein C (APC) resistance through normalized APC sensitivity ratio (nAPCsr) and FibWave will be performed.

Results: The study, initiated on May 25, 2023, has included 19 pregnant patients. Samples from 8 patients have already been analyzed on TGT and nAPCsr (7 weeks n=3, 3 months n=7, 6 months n=6, and 9 months n=2). Preliminary results show a time-dependent increase of both TGT (Figure 1) and nAPCsr (Figure 2). Observed mean nAPCsr values ±SD at the different time points is 6.7 ±1.0; 7.2 ±2.1; 8.2 ±1.6 and 8.9 ±1.1. Due to low recruitment, statistical analysis has not yet been made.

Conclusion(s): Initial findings indicate alterations in the pro-thrombotic state as a function of the trimester using global coagulation tests (TGT and nAPCsr). Further comparison with conventional coagulation tests will allow to measure their ability to reflect individual thrombotic risk to improve patient follow-up.