The article describes a new surgical method in which the levonorgestrel intrauterine system (LNG‑IUS) is fixed to the uterine wall using a special "nail anchoring suture" through a cold knife hysteroscopic system. The aim of this fixation is to reduce the risk of displacement or expulsion of the body, which may impair its contraceptive or therapeutic effect. The method is mainly intended for patients with a significantly enlarged uterine cavity or with repeated displacement or expulsion of the LNG-IUS in the past. The authors set the selection criteria of the material, the operating procedure and the configuration of the tools, and describe the individual steps of the operation in detail on a clinical case. Based on clinical and ultrasound data, they report that the new suturing technique has achieved its intended effectiveness. The method provides firm anchoring of the body and at the same time does not require hysteroscopic control during its removal. According to the authors, it brings improved clinical results and significant economic benefits compared to conventional fixation procedures.