Investigating the association of the dimensions of genital hiatus and levator hiatus with pelvic organ prolapse: a systematic review

Background and hypothesis Pelvic organ prolapse (POP) is a very common and distressing problem that affects women’s quality of life. This systematic review aimed to investigate the association of the dimensions of the genital hiatus and levator hiatus at rest and Valsalva with POP. Methods The Cochrane Library, PubMed, Scopus, Embase and Web of Science were searched on 25 April 2020. All data were analyzed using Review Manager 5.3. Results Of the 1288 papers reviewed, 21 ( n = 5145: 2909 women with POP and 2236 controls) were considered for meta-analysis. Compared with the normal pelvic floor group, the urogenital hiatus size in the POP group was significantly higher at rest (mean difference: 0.49; 95% CI: [0.43, 0.55], P < 0.00001) and at Valsalva (mean difference: 0.79; 95% CI: [0.70, 0.89], P < 0.00001). Also, the levator ani hiatus size in the POP group was significantly higher at rest (mean difference: 0.52, 95% CI: [0.25, 0.78], P < 0.0001) and at Valsalva (mean difference: 1.01; 95% CI: [0.73,1.28], P < 0.00001) compared with that in the normal pelvic floor group. Conclusion This systematic review showed that the sizes of the urogenital hiatus and levator ani hiatus and area of the levator hiatus in the POP group were significantly higher than those in the normal pelvic floor groups in both positions (rest or Valsalva maneuver). Also, in the POP group, the levator hiatus length at rest was significantly lower than that in the Valsalva maneuver.