Safety and efficacy of a 52-mg levonorgestrel-releasing intrauterine system in women with cardiovascular disease

Aim: We sought to examine the safety and efficacy of a 52-mg levonorgestrel-releasing intrauterine system (LNG-IUS), and to evaluate the changes in biomarkers of infection, anemia and cardiovascular conditions after LNG-IUS insertion in women with cardiovascular disease.

Methods: We prospectively followed women with a cardiovascular disease in whom a 52-mg LNG-IUS was inserted between 2009 and 2015. The primary outcome was the frequency of cardiovascular and gynecologic side effects due to the LNG-IUS over the year after LNG-IUS insertion. The secondary outcomes were the changes in menstrual blood loss and biomarkers, e.g., white blood cell count and the levels of C-reactive protein, hemoglobin and brain natriuretic peptide. We also evaluated the 24-month continuation rate of LNG-IUS.

Results: A total of 34 women were prospectively followed-up, including two women with pulmonary hypertension. No cardiovascular side effects were identified during the 1 year after LNG-IUS insertion, other than one case of mild vasovagal reaction at insertion. Neither the white blood cell count nor the C-reactive protein value increased after LNG-IUS insertion. The menstrual blood loss was decreased in most subjects and the median hemoglobin levels increased significantly within 1 year after insertion (P < 0.001 and P = 0.002). Moreover, brain natriuretic peptide levels tended to decrease in correspondence with the hemoglobin elevation (P = 0.074). The 24-month LNG-IUS continuation rate was 97% (95% confidence interval 85-100).

Conclusion: No clinically significant cardiovascular event was identified during the 1 year after 52-mg LNG-IUS insertion among women with cardiovascular disease. The 52-mg LNG-IUS may have specific favorable effects by decreasing the risk of iron deficiency anemia in these women.