Résumé
Background: Few data are available on thrombotic outcomes during pregnancy and puerperium occurring after an initial provoked venous thromboembolic (VTE) event.Objectives: To describe thrombotic outcomes during pregnancy after a first combined oral contraceptive (COC)-associated VTE and the factors associated with recurrence.Methods: This was an international multicentric retrospective study on patients referred for thrombophilia screening from January 1, 2010 to January 1, 2021 following a first COC-associated VTE, including women with neither inherited thrombophilia nor antiphospholipid antibodies and focusing on those who had a subsequent pregnancy under the same thromboprophylaxis treatment. Thrombotic recurrences during pregnancy and puerperium as well as risk factors for recurrence were analyzed.Results: We included 2,145 pregnant women. A total of 88 thrombotic events, 58 antenatal and 29 postnatal, occurred, mostly during the first trimester of pregnancy and the first 2 weeks of puerperium. Incidence rates were 49.6 (37-62) per 1,000 patient-years during pregnancy and 118.7 (78-159) per 1,000 patient-years during puerperium. Focusing on pulmonary embolism, incidence rates were 1.68 (1-4) per 1,000 patient-years during pregnancy and 65.5 (35-97) per 1,000 patient-years during puerperium.Risk factors for antenatal recurrences were maternal hypercholesterolemia and birth of a very small-for-gestational-age neonate. A risk factor for postnatal recurrence was the incidence of preeclampsia.Conclusion: Our multicentric retrospective data show significant rates of VTE recurrence during pregnancy and puerperium in women with a previous VTE event associated with COC, despite a unique low-molecular-weight heparin-based thromboprophylaxis. These results may provide benchmarks and valuable information for designing future randomized controlled trials.