Abstract
The levonorgestrel-releasing intrauterine system (LNG-IUS) is a widely used long-acting reversible contraceptive, offering high efficacy and therapeutic benefits. Although generally safe, mechanical complications such as malposition, perforation, or retained components can occur. We report a case of concealed LNG-IUS arms in a perimenopausal patient following a difficult insertion, illustrating a rare but clinically significant complication. Challenging insertions or removals, particularly in patients with a narrowed cervix or uterine anatomical changes, should raise suspicion for suboptimal device placement. When malposition is suspected, orthogonal two-dimensional (2D) transvaginal ultrasound views can improve visualization and guide management. Awareness of arm retraction within the hormonal sleeve is essential to avoid unnecessary imaging or surgical intervention. Thorough device inspection, including sleeve dissection when required, should be the first step when missing arms are suspected. This report emphasizes the importance of anticipating complications during difficult LNG-IUS insertions or removals and outlines practical diagnostic strategies for suspected malposition, maldeployment, or retained components.