Sinning KM, et al. - Researchers sought to quantify the “normal” adolescent experience after IUD insertion, in order to provide appropriate counseling for future adolescents. levonorgestrel intrauterine system (LNG-IUS) placement in nulliparous adolescents compared to parous adults resulted in more post-insertional discomfort. Despite this, researchers recommended considering this method first-line in this age group.