Adenomyosis is defined thus, by the presence of ectopic endometrial glands and stroma within the myometrium, and hypertrophy and hyperplasia of surrounding adjacent myometrium. 3 The etiology is unclear and the most ABSTRACT Background: The objective of the present study was to observe the efficacy of LNG-IUS in the treatment of heavy menstrual bleeding and dysmenorrhoea associated with adenomyosis. Methods: LNG-IUS was inserted in forty women between 20-50 years of age presenting with heavy menstrual bleeding and dysmenorrhoea associated with adenomyosis diagnosed on transvaginal ultrasonography and followed up after 1 month, 3 months and 6 months of insertion. Subjective assessment of menstrual blood loss was done by pictorial blood loss assessment chart and dysmenorrhoea was assessed on the basis of universal pain assessment tool and side effects were noted at each visit. Results: Mean patients' age was between 31-40 years (72.5%) and the follow up duration was 6 months. Significant improvements in dysmenorrhea, HMB and haemoglobin levels were observed. There was no significant change in the uterine volume. The most common side effect was prolonged vaginal spotting (n=26, 65%) and pain abdomen (n=13, 32.5%). LNG-IUS expulsion was observed in 1 patient (n=1, 2.5%). 3 patients underwent hysterectomy (n=3, 7.5%). The overall success rate of LNG-IUS was 82.5%. Conclusions: The LNG-IUS appears to be an effective method in alleviating dysmenorrhoea and heavy menstrual bleeding associated with adenomyosis during 6 months of study. It may be a valuable long-term alternative for the treatment of adenomyosis in young and perimenopausal women and it is a good strategy to reduce the number of hysterectomies in women with adenomyosis.