Nelson Anita L
a Obstetrics & Gynecology, College of Osteopathic Medicine of the Pacific , Western University of Health Sciences , Pomona , CA , USA.
Expert Rev Clin Pharmacol. 2017 Aug;10(8):833-842. doi: 10.1080/17512433.2017.1341308. Epub 2017 Jun 19.
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.
一种新型的五年期低剂量、小框架、释放左炔诺孕酮的宫内避孕系统（LNG-IUS 12）已被推出，以补充现有的避孕系统。涵盖领域：本文将概述这种新型宫内系统——其组成、作用机制以及其二期和三期临床试验中关于疗效、安全性和耐受性的结果。专家评论：这种新型的LNG-IUS 12提供五年的避孕保护，使用第一年的妊娠率（低于1%），这使其与现有的LNG-IUS 20产品处于同一顶级水平；然而，LNG-IUS 12不像高剂量装置那样经常出现高闭经率。另一方面，这种新型宫内节育器与低剂量的LNG-IUS 8具有相同的较小框架和较窄的插入管，但有效寿命更长。
