Ease of insertion and clinical performance of the levonorgestrel-releasing intrauterine system in nulligravidas

Background: Despite the high contraceptive efficacy and the additional noncontraceptive benefits of the levonorgestrel-releasing intrauterine system (LNG-IUS), concerns persist with respect to its use in nulligravidas. The objective of this study was to evaluate the ease of insertion and clinical performance of the LNG-IUS in nulligravida women up to 1 year after insertion.

Methods: Two cohorts were formed after LNG-IUS insertion, one consisting of 159 nulligravidas and the other of 477 parous women. Each nulligravida women was paired with three parous women who had an LNG-IUS inserted on the same day. Insertion was classified as easy or difficult, and when classified as difficult, the use of Hegar dilators and/or misoprostol and insertion failure were additional factors recorded.

Results: In almost 80% of cases, no difficulty was encountered during insertion, and dilators and misoprostol were seldom required; however, when necessary, dilator use was almost threefold higher in nulligravida women. Insertion failed in one nulligravida women and in two parous women. Contraception was the most common reason for insertion, although some of the women received the LNG-IUS for both contraceptive and therapeutic purposes, including heavy menstrual bleeding, hematologic diseases, warfarin use, endometriosis-associated pain and following kidney or liver transplantation. The clinical performance of the device showed zero pregnancy rate, expulsion rates of ∼4/100 women-year and 1-year continuation rate of over 90% in both groups.

Conclusions: The LNG-IUS is suitable for use by nulligravidas. It is simple to insert, and its clinical performance in nulligravidas is similar to that found in parous women.