Hysteroscopic surgery is widely used for the treatment of patients suffering from menorrhagia. In different studies, pretreatment of the endometrium with GnRH analogues (GnRH-a) prior to endometrial ablation has been reported to increase the success rate, as well as to reduce the menstrual blood flow, accounting for a significantly higher postoperative amenorrhea rate (42% in pretreated patients vs. 24% in those receiving no pretreatment). The aim of pretreatment is not only to obtain a thin endometrium but also to reduce the size and vascularization of myomas being treated. In our study, GnRH-a administration prior to endometrial ablation was shown to have the following advantages: improved hysteroscopic view, reduced blood loss, absorption of uterine distending fluid and higher postoperative amenorrhea rates. Prior to hysteroscopic myoma resection, pretreatment with GnRH-a may be particularly indicated for all myomas with a diameter of more than 3 cm and/or with an intramural portion, or for patients suffering from secondary anemia. GnRH-a pretreatment is thus indicated before endometrial ablation, and in most cases, before hysteroscopic resection of submucous myomas, and combined medical and surgical therapy has clear benefits in the treatment of bleeding disorders.