Objectives: Transvaginal natural orifice transluminal endoscopic surgery (vNOTES) and transumbilical laparoendoscopic single-site surgery (LESS) have shown the prospection as minimally invasive procedures. Here we aimed to compare ovarian cystectomy assisted by vNOTES and by LESS for ovarian mature cystic teratoma (OMCT).

Material and methods: A total of 81 premenopausal women with OMCT were randomized to undergo ovarian cystectomy assisted by either vNOTES (n = 41) or LESS (n = 40). The main outcome was the operative time. Secondary outcomes included the length of hospital stay, visual analog scale (VAS) pain scores, abdominal contamination by teratoma contents, and intraoperative and postoperative complications.

Results: There were no intergroup differences in age, body mass index, tumor size, or bilaterality of tumor. The operative time for the vNOTES group was significantly shorter than that for the LESS group (68.41 ± 20.92 min vs 85.05 ± 32.94 min, p = 0.008). The highest VAS pain score 24 hours postoperatively was 1.21 ± 0.48 in the vNOTES group and 2.43 ± 0.57 in the LESS group (p < 0.001). Twenty-four of the 40 patients in the LESS group experienced teratoma rupture intraoperatively, leading to abdominal contamination by the teratoma content, while 5 abdominal contamination was observed in the vNOTES group （p = 0.005. No significant differences between the two groups were observed in the other outcomes.

Conclusions: vNOTES assisted ovarian cystectomy has short operative time, fast recovery, no scarring, less pain, and low rate of abdominal contamination. Consequently, vNOTES might be superior to LESS for treating OMCTs.