Background:Although repair augmented with mesh has been proved its priority in anatomical and functional recovery after anterior compartment reconstruction,the data about posterior compartment are scarce.The aim of this study was to compare bowel functional outcome of posterior vaginal compartment repair with and without mesh in patients with pelvic organ prolapse (POP).Methods:This was a prospective,double-blind,clinical pilot study of 22 postmenopausal women with symptomatic POP (overall POP-quantification [POP-Q] Stage Ⅲ-ⅣV) who underwent total pelvic floor reconstruction.Patients were grouped according to the use of mesh for posterior vaginal compartment repair:A mesh group and a nonmesh group.POP-Q stage,the pelvic floor impact questionnaire short form-7 (PFIQ-7) and anorectal manometry were evaluated before and 3 months after surgery.Anatomical success was defined as POP-Q Stage Ⅱ or less.A t-test was used to compare preoperative with postoperative data in the two groups.Results:Totally,17 (71％) were available for the follow-up.POP-Q measurements improved significantly compared to baseline (P ＜ 0.05) in both groups.No recurrence was observed.Subjects in both groups reported improvement in pelvic floor symptoms,and there was no significant difference in the PFIQ-7 score between groups at follow-up (P ＞ 0.05).Compared with baseline,the nonmesh group exhibited a statistically significant decrease in anal residual pressure,a significant increase in the anorectal pressure difference during bowel movement,and a reduced rate ofdyssynergia defecation patt (P ＜ 0.05).Conclusions:Provided there is sufficient support for the anterior wall and apex of vagina with mesh,posterior compartment repair without mesh may be as effective as repair with mesh for anatomical recovery while providing better anorectal motor function.