摘要Objectives:This research aimed to investigate changes in defecation sensory threshold and related factors in pa-tients with posterior vaginal wall prolapse.Methods:A total of 214 patients with pelvic organ prolapse were recruited between October 2019 to January 2021.All patients underwent a defecation sensory threshold examination,physical examination,and pelvic floor ultrasound examination.Factors related to the defecation sensory threshold were analyzed.Results:(1)Among the participants,57 patients(26.6％)had a defecation sensory threshold of more than 90 ml.Patients with a threshold＞90 ml showed higher scores of defecation dysfunction in the Constipation Scoring System(CSS)score(pp=0.003)and higher scores of constipation in the Colorectal-anal Distress Inventory 8(CRADI-8)score(pp=0.002).(2)The defecation sensation threshold positively correlated with the Ap point(r=0.448,p＜0.001),the Bp point(r=0.345,p=0.009),the area of the levator-ani hiatus measured by trans-vaginal ultrasound(r=0.403,p=0.002),and parity(r=0.355,p=0.007).Conclusions:Patients diagnosed with pelvic organ prolapse commonly experience an increased threshold of defecation sensation.Elevated thresholds were associated with more frequent constipation symptoms.Addi-tionally,the severity of posterior pelvic prolapse positively correlated with the defecation sensory threshold.