Efficacy of dienogest in thinning the endometrium before hysteroscopic surgery

To investigate the efficacy of administration of dienogest to thin the endometrium before hysteroscopic surgery and to evaluate the surgical outcome.

Retrospective clinical study (Canadian Task Force classification III).

Community hospital.

Twenty-six patients who underwent hysteroscopic surgery for treatment of endometrial polyps or submucous myomas <25 mm.

Before hysteroscopic surgery, 13 patients (dienogest group) received 2 mg dienogest orally for 2 weeks, and 13 patients (GnRH group) received a gonadotropin-releasing hormone agonist subcutaneously 1 to 3 times every 4 weeks, and 4 of those received hormone therapy after surgery. Endometrial thickness, serum estradiol and progesterone concentrations, duration of surgery, weight of tissue removed, surgical field visualization, and time to resumption of spontaneous menstruation were recorded.

Endometrial thickness decreased from approximately 7.0 mm to 3.9 mm in the dienogest group. Duration of surgery and weight of tissue removed were similar between groups. The surgical field was clearly visualized in 12 patients in each group. Spontaneous menstruation resumed at approximately 22.0 days after hysteroscopic surgery in the dienogest group; in contrast, no resumption of spontaneous menstruation was observed within the first postoperative month in the GnRH group. No patients had perioperative complications, and none exhibited any residual tumor.

Administration of dienogest for 2 weeks thinned the endometrium and yielded favorable surgical outcomes, similar to those with GnRH agonists. Administration of dienogest may be an effective and convenient treatment before hysteroscopy.