Efficacy of etonogestrel subcutaneous implants versus the levonorgestrel-releasing intrauterine system in the conservative treatment of adenomyosis.

To evaluate the clinical efficacy of etonogestrel subcutaneous implant (ENG-SCI) with that of the levonorgestrel-releasing intrauterine system (LNG-IUD) for adenomyosis treatment. A prospective randomized cohort study was conducted including 108 patients (50 patients in ENG-SCI group and 58 in the LNG-IUD group) with adenomyosis from January 2019 to July 2021. After 3 months of treatment, both ENG-SCI group and LNG-IUD group showed significant improvement in patients' visual analog scale, pictorial blood loss assessment chart (PBAC), and uterine volume (P ＜ 0.05). The uterine volume of patients in LNG-IUD group decreased more significantly than that in the ENG-SCI group since 3 months of treatment. The PBAC score in the LNG-IUD group improved better than that in the ENG-SCI group since 6 months of treatment (P ＜ 0.05). No significant difference in the occurrence rate of ideal vaginal bleeding patterns and the hemoglobin levels between the two groups was observed. The ENG-SCI group had a higher probability of weight gain and progesterone-related side effects (P ＜ 0.05). Both ENG-SCI and LNG-IUD were effective in treatment of adenomyosis. However, LNG-IUD had a more significant effect in treating adenomyosis-related dysmenorrhea, excessive menstrual flow, anemia, and uterine enlargement, with relatively fewer side effects.