Risk factors of treatment discontinuation due to uterine bleeding in adenomyosis patients treated with dienogest

Aim: Adenomyosis patients treated with dienogest are considered to be at higher risk of uterine bleeding; however, the mechanisms which cause severe uterine bleeding in those patients are unknown. This study aims to investigate the risk factors of uterine bleeding among adenomyosis patients treated with dienogest.

Material and methods: Clinical data of 51 adenomyosis patients treated with dienogest were retrospectively collected from their medical records. The impact of potential risk factors (age, sagittal square area of the uterus before treatment, and estradiol at the third month of treatment) and confounders (hemoglobin before treatment and prior medical treatments) on the time to treatment discontinuation due to uterine bleeding was assessed using log-rank tests and a Cox proportional hazard model.

Results: Age (< 38 years, P = 0.004), hemoglobin before treatment (<12 g/dL, P = 0.047), and estradiol at the third month of treatment (≥ 60 pg/mL, P = 0.027) had statistically significant effects on the time to treatment discontinuation due to uterine bleeding. Age was still statistically significant after controlling for hemoglobin (P = 0.023).

Conclusion: Adenomyosis patients treated with dienogest are at higher risk of treatment discontinuation due to uterine bleeding, especially when they are of younger age, have anemia before treatment, and/or have mildly suppressed or unsuppressed estradiol after they started dienogest treatment. Clinicians should pay special attention when they prescribe dienogest for such patients.