LAUSR

The aim of this study was to evaluate the changing pattern of bone mineral density (BMD) levels after 3 years of dienogest use post endometrioma surgery and investigate the possible predictive factors for BMD reduction. This retrospective study included 44 reproductive-aged women who took dienogest (2 mg/day) and followed up BMD for 3 years after laparoscopic endometrioma surgery from July 2013 to December 2018. In addition, to investigate the predictive factors in the group with decreased BMD, analysis was added for patients with decreased BMD after taking dienogest for 1 year post laparoscopic endometrioma surgery. After 3 years of treatment with dienogest, BMD of both the lumbar spine (− 4.4%) and femur neck (− 3.6%) decreased significantly compared to the baseline levels. Bone loss predominantly occurred during the first year of treatment in the lumbar spine (− 2.4%) and gradually decreased with time during the treatment period. The predictive factors for BMD reduction after dienogest use were evaluated based on a 1-year change in BMD levels of 160 women, but no associated factors were found. This study demonstrated that dienogest use for 3 years was associated with a significant and gradual decrease in BMD and no predictive factors for BMD reduction during the first year of treatment with dienogest were found. These results may be useful in counseling patients regarding long-term effects of dienogest use on reducing BMD levels so that appropriate preventive measures can be taken.