Drospirenone-containing oral contraceptive pills and the risk of venous and arterial thrombosis: a systematic review.

Previous studies have provided conflicting results regarding the effect of drospirenone-containing oral contraceptive pills (OCPs) on the risk of venous and arterial thrombosis. To conduct a systematic review to assess the risk of venous thromboembolism (VTE), myocardial infarction (MI), and stroke in individuals taking drospirenone-containing OCPs. We systematically searched CINAHL, the Cochrane Library, Dissertation & Abstracts, EMBASE, HealthStar, Medline, and the Science Citation Index from inception to November 2012. We included all case reports, observational studies, and experimental studies assessing the risk of venous and arterial thrombosis of drospirenone-containing OCPs. Data were collected independently by two reviewers. A total of 22 studies [six case reports, three case series (including 26 cases), and 13 comparative studies] were included in our systematic review. The 32 identified cases suggest a possible link between drospirenone-containing OCPs and venous and arterial thrombosis. Incidence rates of VTE among drospirenone-containing OCP users ranged from 23.0 to 136.7 per 100 000 woman-years, whereas those among levonorgestrel-containing OCP users ranged from 6.64 to 92.1 per 100 000 woman-years. The rate ratio for VTE among drospirenone-containing OCP users ranged from 4.0 to 6.3 compared with non-users of OCPs, and from 1.0 to 3.3 compared with levonorgestrel-containing OCP users. The arterial effects of drospirenone-containing OCPs were inconclusive. Our systematic review suggests that drospirenone-containing OCP use is associated with a higher risk for VTE than both no OCP use and levonorgestrel-containing OCP use.