Gynecology · Published 2026-03-10 · DOI 10.26442/20795696.2026.1.203570
Background. Endometriosis is a chronic, recurrent condition requiring long-term medical therapy, particularly in the absence of pregnancy plans. Dienogest (DNG) is considered a first-line treatment due to its comprehensive mechanism of action. However, there remains a lack of studies objectively assessing the dynamics of endometriotic lesions via magnetic resonance imaging (MRI) during DNG therapy. The need for such data, including evaluation of its effect on pain syndrome and ovarian reserve, defines the relevance of this study. Aim. To assess the dynamics of endometriotic lesions, pain intensity, and ovarian reserve parameters in patients with endometriosis receiving DNG therapy. Materials and methods. A prospective study was conducted involving 71 women with MRI-confirmed endometriosis (mean age 32.1 years) who were not indicated for surgical treatment. Patients received DNG 2 mg/day (Zafrilla®) continuously for at least 6 months (mean 8.5 months). Assessments performed before treatment initiation and after 6 months included: size of endometriotic lesions (deep endometriosis and endometriomas) using MRI; pain intensity; quality of life (SF-12 questionnaire); and serum levels of anti-Müllerian hormone (AMH), estradiol, and CA-125. Statistical analysis was performed using the Wilcoxon signed-rank test. Results. DNG therapy resulted in a significant reduction in the volume of deep endometriosis foci by 4 times and endometriotic cysts by 5 times. A decrease in pain intensity was observed: the dysmenorrhea score decreased from 6.0 to 0 (p 0.0001), and the pelvic pain index decreased from 2.0 to 0.2 (p 0.0001). Pelvic pain was resolved in 93.2% of patients. AMH and estradiol levels showed no statistically significant change, while CA-125 levels decreased by half. The main adverse effect was acyclic bleeding (33.9%), which did not lead to therapy discontinuation in most cases. Conclusion. Continuous DNG therapy demonstrated high efficacy in the regression of endometriotic lesions and improvement in the quality of life of patients with endometriosis. An important clinical advantage is the preservation of ovarian reserve during treatment. Thus, dienogest (Zafrilla®) can be considered an effective and safe option for the long-term conservative management of endometriosis.
Abstract from DOAJ. Public domain (CC0 1.0).
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