Aim: Dienogest (DNG) is highly effective for relieving pain caused by endometriosis and adenomyosis. However, women with severe uterine swelling due to adenomyosis who take DNG usually experience metrorrhagia. This study aimed to examine the safety of DNG usage in women with adenomyosis.
Methods: This study included 20 women who were prescribed DNG for adenomyosis in our hospital from January 2016 to December 2016. We retrospectively analyzed women's clinical background characteristics (age, the use of the gonadotropin-releasing hormone agonist as pre-treatment of DNG, the uterus size [major axis, minor axis, maximum thickness in the myometrium, and length of the uterine body] by transvaginal ultrasonography [TVUS], hemoglobin level, and the presence of metrorrhagia during treatment). These variables were compared between the DNG continuation and discontinuation groups using the Mann-Whitney U test.
Results: Thirteen women continued DNG, and seven discontinued DNG within 12 months because of metrorrhagia. The uterine size was significantly larger in the discontinuation group than in the continuation group. All uterine measurements had high Spearman rank correlation coefficients (ρ > 0.8, P < 0.05). In six of seven cases in the discontinuation group, adenomyosis was in the anterior wall. Measuring the uterus size and locating adenomyosis by TVUS are simple methods of predicting DNG discontinuation.
Conclusion: We consider that DNG can be safely administered in women with adenomyosis if the uterine size is <6 cm in the minor axis and the main lesion of adenomyosis is located in the posterior uterine wall.
Keywords: adenomyosis; dienogest; metrorrhagia; ultrasound; uterine size.
© 2021 Japan Society of Obstetrics and Gynecology.