ObjectiveTo evaluate the feasibility and safety of leaving the submucous myoma (SM) in the uterine cavity after office hysteroscopic enucleation. Study DesignProspective multicenter study including patients who had a single SM diagnosed by transvaginal ultrasounds with surgical indication. Office hysteroscopic enucleation of the SM was performed using a 5 mm continuous flow office hysteroscope with a 2.9 mm rod lens optical system and a 5 Fr operative channel. After the SM was released preserving the pseudo capsule using cold instruments, it was left into the uterine cavity. The primary endpoint was the proportion of patients without evidence of the myoma at the transvaginal ultrasound performed after 90 days from surgery. ResultsBetween January 1st, 2018, and March 31st, 2020, a total of 204 patients were enrolled. Most patients were nulliparous and reported abnormal uterine bleeding as the leading symptom. 76.5 % of enucleated myomas had a diameter ranging between 1.5 and 2.5 cm, and 81.4 % of SMs were of G0 or G1. Hysteroscopic procedures had a mean duration of 23.2 ± 10.5 min. The operative time was associated with the SM grade and size. All hysteroscopic procedures were completed. A vasovagal reaction was observed in 3 women (1.5 %), and minimal post-operative bleeding was reported after 7 procedures (3.4 %). None reported pelvic pain or vaginal discharges/bleeding during follow-up. The average patient satisfaction from surgery was 4.59 (5-points Likert scale). The level of patient satisfaction was not associated with the grade and the size of the myoma. In 192 (94.12 %; 98 %CI: 89.03–96.93 %) out of 204 patients, the SM was absent at the transvaginal ultrasound performed at the follow-up end. A higher prevalence of G2 SMs and lower prevalence of G1 SMs were observed among patients with evidence of the myoma after 90 days from the surgery. ConclusionOffice hysteroscopic myomectomy with SM enucleation without mass extraction appears safe, well-tolerated, and effective in at least 89 % of patients. G2 SMs may be the factor associated with the procedure's failure.