Thromboembolic events in women exposed to hormonal contraception or cyproterone acetate in 2012: a cross-sectional observational study in 30 French public hospitals.

Background: In the context of the European reassessment of the benefit-risk balance of hormonal contraceptives, French data about thromboembolic events were requested.

Objective: The aim of this study was to determine the number of patients exposed to hormonal contraception or cyproterone acetate among hospitalized females diagnosed with a thromboembolic event in 2012, to retrospectively analyze specific risk factors of venous and arterial thromboembolism and to assess the magnitude of the under-reporting of such events to the national pharmacovigilance system.

Methods: This cross-sectional study included 15- to 49-year-old women with pulmonary embolism, venous cerebral thrombosis, ischemic stroke, or myocardial infarction, hospitalized in 2012, and identified within the computerized hospital databases of 30 French teaching hospitals.

Results: Among the 2,966 cases identified, 803 (27.1 %) patients had been exposed to a hormonal contraceptive (747) or to cyproterone acetate (56). Among these, there were 452 venous thromboembolic events (VTEs) and 351 arterial thromboembolic events (ATEs). Age ≥40 years and personal thrombophilia diagnosed after the event were the main VTE risk factors, while current smoking and age ≥40 years were the main ATE risk factors. The mean number of associated risk factors was significantly lower for VTE than for ATE (1.1 vs 2.3). The proportion of cases with no risk factors was higher for third- and fourth-generation than for first- and second-generation combined oral contraceptives. Overall, the under-reporting rate was 92.5 % (95 % CI 70.0-97.3).

Conclusion: This study highlighted the need to strengthen the knowledge of patients and health professionals about thromboembolic risk factors at the first prescription and renewal of hormonal contraceptives.