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1. THROMBOEMBOLIC DISORDERS AND OTHER VASCULAR PROBLEMS a. Thromboembolism An increased risk of thromboembolic and thrombotic disease associated with the use of oral contraceptives is well established. Case control studies have found the relative risk of users compared to non-users to be 3 for the first episode of superficial venous thromboembolic disease, 4 to 11 for deep vein thrombosis or pulmonary embolism, and 1.5 to 6 for women with predisposing conditions for venous thromboembolic disease (2,3,19Ð 24). Cohort studies have shown the relative risk to be somewhat lower, about 3 for new cases and about 4.5 for new cases requiring hospitalization (25). Text Continues Below
The risk of thromboembolic disease associated with oral con-traceptives is not related to length of use and disappears after pill use is stopped (2). Several epidemiologic studies indicate that third generation oral contraceptives, including those containing desogestrel, are associated with a higher risk of venous thromboembolism than certain second generation oral contraceptives (102Ð 104). In general, these studies indicate an approximate two-fold increased risk, which corresponds to an additional 1Ð 2 cases of venous thromboembolism per 10,000 women-years of use. However, data from additional studies have not shown this two-fold increase in risk. A two-to four-fold increase in relative risk of post-operative thromboembolic complications has been reported with the use of oral contraceptives (9,26). The relative risk of venous thrombosis in women who have predisposing conditions is twice that of women without such medical conditions (9,26). If feasible, oral contraceptives should be discontinued at least four weeks prior to and for two weeks after elective surgery of a type associated with an increase in risk of thromboembolism and during and following prolonged immobilization. Since the immediate postpartum period is associated with an increased risk of thrombo-embolism, oral contraceptives should be started no earlier than four weeks after delivery in women who elect not to breast feed. Page: << Prev | 1 | 2 | 3 | 4 | 5 | Next >>
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