GyneFix levonorgestrel-releasing intrauterine system for Chinese patients: a preliminary retrospective self-controlled observational study

BACKGROUND: Device expulsion is a common complication of the levonorgestrel-releasing intrauterine system (LNG-IUS), with a higher incidence among high-risk patients presenting with enlarged uterine cavities, cervical laxity or menorrhagia. At present, no commercially available frameless LNG-IUS is marketed in mainland China, leaving these high-risk patients without effective clinical interventions. OBJECTIVES: This study describes the assembly procedures and clinical application of a modified frameless LNG-IUS based on the GyneFix anchoring system (GyneFix-LNG-IUS), and the intrauterine retention performance is preliminarily assessed alongside its capacity to reduce expulsion risk. METHODS: This was a retrospective, self-controlled, observational prognostic study. A total of 15 consecutive cases were included. All included cases had a documented history of conventional LNG-IUS expulsion and multiple high-risk factors for expulsion, including enlarged uterine cavities, menorrhagia and cervical laxity. The modified device was assembled using the GyneFix anchoring component and a standard LNG-IUS, and inserted under hysteroscopic guidance. The 12-month device retention rate and its corresponding 95% confidence interval were calculated. RESULTS: All insertions of GyneFix-LNG-IUS were completed successfully in a single attempt, and no intra-operative or post-operative complications were recorded. Gynaecological ultrasound data acquired at 12 months or longer after placement were collected for all cases. Ultrasonographic examinations confirmed that all devices were positioned within the uterine fundus, with no signs of downward displacement or expulsion observed. The 12-month retention rate was 100% (95% CI: 78.2%-100%). CONCLUSIONS: Based on the limited data from this small cohort, the modified GyneFix-LNG-IUS features simple assembly and smooth intrauterine insertion. Preliminary findings indicate that this device may reduce expulsion risk among patients prone to conventional LNG-IUS loss. It may serve as a viable clinical alternative in settings without access to commercial frameless LNG-IUS.