title: Assessment of the use of two new low-dose levonorgestrel-releasing intrauterine systems as contraceptives.
abstract: Evaluation of: Gemzell-Danielsson K, Schellschmidt I, Apter D. A randomized, Phase II study describing the efficacy, bleeding profile, and safety of two low-dose levonorgestrel-releasing intrauterine contraceptive systems and Mirena. Fertil. Steril. 97(3), 616-622.e3 (2012). A randomized, open-label, Phase II study was conducted in 37 centers in five European countries to assess the optimal dose for a new contraceptive levonorgestrel intrauterine system (LNG-IUS). Overall, 742 parous or nulliparous women aged 21-40 years were allocated to receive a LNG-IUS that initially releases 12 µg/day (LNG-IUS(12)) or 16 µg/day (LNG-IUS(16)) in vitro or the currently available device that releases 20 µg/day (LNG-IUS(20)). The two new devices are shorter than the current one. Pearl Indices of 0.17, 0.82 and 0.00 for the LNG-IUS(12), LNG-IUS(16) and LNG-IUS(20), respectively, reflect the contraceptive efficacy of these devices. The mean number of bleeding and spotting days decreased in all three groups; however, this decrease was more significant in LNG-IUS(20) users. Placement of the new shorter devices was considered simple by providers, while patients reported significantly less pain with the two new devices compared with the current one. This study provided further insight into the development of two new LNG-IUS devices as contraceptives, with the additional possibility of using them to treat heavy menstrual bleeding or as endometrial protection during estrogen therapy.
authors.affiliation: Human Reproduction Unit, Department of Obstetrics & Gynecology, School of Medical Sciences, University of Campinas (UNICAMP), Caixa Postal 6181, 13084-971 Campinas, SP, Brazil. bahamond@caism.unicamp.br
authors.forename: Luis
authors.initials: L
authors.lastname: Bahamondes
authors.forename: M Valeria
authors.initials: MV
authors.lastname: Bahamondes
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D011247:Pregnancy; D003280:Contraceptives, Oral, Synthetic / Q000008:administration & dosage / Q000627:therapeutic use; D004305:Dose-Response Relationship, Drug; D005060:Europe; D007436:Intrauterine Devices, Medicated; D016912:Levonorgestrel / Q000008:administration & dosage / Q000627:therapeutic use; D008796:Metrorrhagia / Q000188:drug therapy; D049168:Pregnancy, Unplanned; D013997:Time Factors; D016896:Treatment Outcome; D016032:Randomized Controlled Trials as Topic; D017322:Clinical Trials, Phase II as Topic
chemical_list: D003280:Contraceptives, Oral, Synthetic; D016912:Levonorgestrel