Oral anticoagulant therapy does not modify the bleeding pattern associated with the levonorgestrel-releasing intrauterine system in women with thrombophilia and/or a history of thrombosis

Abstract Background Progestogen-only contraceptives (POCs) are suitable for women with thrombophilia and/or a history of venous thromboembolism (VTE). Several of these women, however, use oral anticoagulant therapy (OAT), which can impair the bleeding pattern associated with POC use. We evaluated the effects of OAT use on the bleeding pattern associated with the levonorgestrel-releasing intrauterine system (LNG-IUS) in women with thrombophilia and/or a history of VTE. Study Design This prospective cohort study followed two groups of women, all of whom were thrombophilic and/or had a history of VTE: OAT users and nonusers. Bleeding patterns, blood pressure, body mass index (BMI), weight, complete blood count and waist circumference were compared between the two groups before and 6 and 12 months after LNG-IUS insertion. Results The patient cohort consisted of 33 women aged 18 to 45 years old, including 16 OAT users and 17 nonusers. Body weight increased by 3.9% and BMI by 3.8% in OAT users 12 months after LNG-IUS insertion. Hemoglobin and hematocrit levels increased by approximately 10% in both groups. There was no difference between the groups in bleeding patterns, with amenorrhea being the most frequent pattern in both groups (41.2% each) 12 months after LNG-IUS insertion. OAT did not increase the frequency of prolonged and/or frequent bleeding. Conclusion OAT users and nonusers had similar bleeding patterns after insertion of the LNG-IUS. Hemoglobin and hematocrit levels increased in both groups.