Department of Family Medicine, Université de Clermont-Ferrand, Clermont-Ferrand, France.
Contraception. 2011 Nov;84(5):e23-30. doi: 10.1016/j.contraception.2011.06.008. Epub 2011 Aug 4.
Combined oral contraceptives (COC) increase the risk of venous thromboembolism (VTE), but the risk of recurrent VTE is not precisely determined. In this retrospective cohort study, we sought the risk factors for recurrence after a first VTE that occurred in women taking COC.
Time-to-event analysis was done with Kaplan-Meier estimates. In total, 172 patients were included (43% with pulmonary embolism): 82% had no other clinical risk factor for VTE.
Among the 160 patients who stopped anticoagulation, the cumulative incidence of recurrent VTE was 5.1% after 1 year and 14.2% after 5 years. Significant factors associated with recurrence were renewed use of COC [hazard ratio (HR)=8.2 (2.1-32.2)], antiphospholipid syndrome [HR=4.1 (1.3-12.5)] and protein C deficiency or factor II G20210A [HR=2.7 (1.1-7)]. Pure-progestin contraception [HR=1.3 (0.5-3.0)] or factor V Leiden [HR=1.3 (0.5-3.4)] did not increase recurrence. Postsurgical VTE had a lower risk of recurrence [HR=0.1 (0.0-0.9)].
Further studies are warranted to determine whether testing for antiphospholipid syndrome, protein C deficiency or the factor II G20210A could modify the duration of anticoagulation. This study confirms the safety of pure-progestin contraception.
口服避孕药（COC）会增加静脉血栓栓塞（VTE）的风险，但复发性 VTE 的风险尚不清楚。在这项回顾性队列研究中，我们旨在确定服用 COC 的女性首次发生 VTE 后复发的危险因素。
采用 Kaplan-Meier 估计进行时间事件分析。共纳入 172 例患者（43%患有肺栓塞）：82%无其他 VTE 临床危险因素。
在 160 例停止抗凝的患者中，1 年后和 5 年后复发性 VTE 的累积发生率分别为 5.1%和 14.2%。与复发相关的显著因素包括重新使用 COC[风险比（HR）=8.2（2.1-32.2）]、抗磷脂综合征[HR=4.1（1.3-12.5）]和蛋白 C 缺乏或因子 II G20210A[HR=2.7（1.1-7）]。单纯孕激素避孕[HR=1.3（0.5-3.0）]或因子 V Leiden[HR=1.3（0.5-3.4）]并未增加复发风险。手术后 VTE 的复发风险较低[HR=0.1（0.0-0.9）]。
需要进一步研究以确定是否检测抗磷脂综合征、蛋白 C 缺乏或因子 II G20210A 是否可以改变抗凝时间。本研究证实了单纯孕激素避孕的安全性。
