Levonorgestrel-releasing intrauterine system (LNG-IUS 12) for prevention of pregnancy for up to five years.

INTRODUCTION: A new five-year low dose, smaller-framed, levonorgestrel-releasing intrauterine contraceptive system (LNG-IUS 12) has been introduced to complement the currently available systems. Areas Covered: This article will provide an overview of this new intrauterine system - its composition and its mechanisms of action as well as the results of the Phase II and III clinical trials of its efficacy, safety and tolerability. Expert Commentary: This new LNG-IUS 12 provides five-year contraceptive protection a pregnancy rate (less than 1%) in first year of use, which puts it into the top tier with the existing LNG-IUS 20 products; however, the LNG-IUS 12 does not have the high rates of amenorrhea often seen with the higher dose devices. On the other hand, this new IUD shares the smaller frame and narrower insertion tube with the lower dose LNG-IUS 8, but offers longer effective life.