This study aimed to assess the feasibility and the short-and long-term efficacy of hysteroscopic myomectomy for submucous myomas with intramural development [grade 1 (G1) and grade 2 (G2)] by using non-electrical "cold" loops and to verify the role of preoperative variables on surgical outcomes. Symptomatic (bleeding and infertility) premenopausal patients with the diagnosis of submucous myoma at transvaginal sonography, and with G1 and G2 grading at sonohysterography, were included in this prospective study. Hysteroscopic myomectomy was performed by the combined monopolar electrical slicing and traction-andleverage manoeuvres by non-electrical "cold" loops. One hundred fifty-nine patients were recruited, and 169 procedures were performed. Operating time, fluid deficit, complications and complete resection at first procedure (perioperative outcomes) and persisting symptoms and additional surgery for persisting symptoms (long-term outcomes) were not significantly different for G1 vs. G2 myomas. Perioperative outcomes were significantly different when comparing myoma mean diameter <3.0 vs. ≥3.0 cm (75th percentile). Multivariate analysis and multiple regression analysis proved that myoma mean diameter was the only significant variable for surgical outcomes. Hysteroscopic myomectomy by non-electrical "cold" loops is an effective and efficient treatment for submucous myomas with intramural development. Myoma mean diameter is the only significant preoperative variable for perioperative outcome, while myoma grading loses its role as a prognostic factor.