To evaluate the effectiveness and tolerability of dienogest in patients with endometriosis in real-world clinical practice.

This cross-sectional observational study was based on a self-administered questionnaire in which patients retrospectively reported their symptoms and quality of life before dienogest initiation, as well as perceived treatment effectiveness and tolerability. The questionnaire was distributed to patients followed for endometriosis within a regional endometriosis care network (April 2024–September 2025). Participants assessed symptom improvement, overall quality of life before and during treatment, the frequency of adverse events, and treatment continuation or discontinuation. Changes in quality of life before and after treatment were analysed using the Wilcoxon test.

A total of 146 patients were included. Complete resolution of dysmenorrhea was reported by 44.7% of patients with baseline dysmenorrhea (55/123). Overall quality of life significantly improved under treatment (4.4 ± 2.3 vs 5.5 ± 2.6; p<0.001). All patients reported at least one adverse event; the most frequent were fatigue (63.0%), decreased libido (58.3%), and mood disturbances (50.7%). Treatment was discontinued by 40.4% of patients, mainly due to adverse events. Some symptom improvements and adverse events varied according to treatment duration.

In this real-world patient-reported study, patients reported improvement under dienogest treatment, particularly for dysmenorrhea and overall quality of life. However, frequent adverse events and treatment discontinuation suggest that tolerability may limit long-term adherence.