Measurement of changes in uterine and fibroid volume during treatment of heavy menstrual bleeding (HMB)

• Published in: Human reproduction open 2023, Vol.2023 (3), p.hoad021-hoad021
• Main Authors: Yin, K, Whitaker, L, Hojo, E, McLenachan, S, Walker, J, McKillop, G, Stubbs, C, Priest, L, Cruz, M, Roberts, N, Critchley, H
• Format: Article
• Language: English
• Subjects: Care and treatment; Development and progression; Leiomyoma; Menorrhagia; Original; Physiological aspects; Uterus
• ISSN: 2399-3529; 2399-3529
• DOI: 10.1093/hropen/hoad021

Abstract STUDY QUESTION Does application of an unbiased method for analysis of magnetic resonance (MR) images reveal any effect on uterine or fibroid volume from treatment of heavy menstrual bleeding (HMB) with three 12-week courses of the selective progesterone receptor modulator ulipristal acetate (SPRM-UPA)? SUMMARY ANSWER Application of an unbiased method for analysis of MR images showed that treatment of HMB with SPRM-UPA was not associated with a significant reduction in the volume of the uterus or in the volume of uterine fibroids. WHAT IS KNOWN ALREADY SPRM-UPA shows therapeutic efficacy for treating HMB. However, the mechanism of action (MoA) is not well understood and there have been mixed reports, using potentially biased methodology, regarding whether SPRM-UPA has an effect on the volume of the uterus and fibroids. STUDY DESIGN, SIZE, DURATION In a prospective clinical study (with no comparator), 19 women with HMB were treated over a period of 12 months with SPRM-UPA and uterine and fibroid size were assessed with high resolution structural MRI and stereology. PARTICIPANTS/MATERIALS, SETTING, METHODS A cohort of 19 women aged 38–52 years (8 with and 11 without fibroids) were treated with three 12-week courses of 5 mg SPRM-UPA given daily, with four weeks off medication in-between treatment courses. Unbiased estimates of the volume of uterus and total volume of fibroids were obtained at baseline, and after 6 and 12 months of treatment, by using the Cavalieri method of modern design-based stereology in combination with magnetic resonance imaging (MRI). MAIN RESULTS AND THE ROLE OF CHANCE Bland–Altman plots showed good intra-rater repeatability and good inter-rater reproducibility for measurement of the volume of both fibroids and the uterus. For the total patient cohort, two-way ANOVA did not show a significant reduction in the volume of the uterus after two or three treatment courses of SPRM-UPA (P = 0.51), which was also the case when the groups of women with and without fibroids were considered separately (P = 0.63). One-way ANOVA did not show a significant reduction in total fibroid volume in the eight patients with fibroids (P = 0.17). LIMITATIONS, REASONS FOR CAUTION The study has been performed in a relatively small cohort of women and simulations that have subsequently been performed using the acquired data have shown that for three time points and a group size of up to 50, with alpha (Type I Error) and beta (Type II Error) set to 95% sig