Pelvic Organ Prolapse Stage and the Relationship to Genital Hiatus and Perineal Body Measurements

Objectives: This study aimed to describe the relationship between genital hiatus (GH) and perineal body (PB) measurements with increasing pelvic organ prolapse (POP) stage in a large cohort of women referred to Urogynecology clinic for pelvic floor disorders.

Methods: Retrospective chart review of all new patients seen in an academic Urogynecology clinic between January 2007 and September 2011 was performed. Data were extracted from a standardized intake form. All patients underwent a Pelvic Organ Prolapse Quantification (POPQ) examination. Descriptive statistics compared the study population. Analysis of variance was used to compare GH and PB measurements by prolapse stage. Fisher least significant differences were used for post hoc comparisons of means between prolapse stages. Pearson correlations were used to evaluate the associations between GH and PB measurements and patient characteristics.

Results: A total of 1595 women with POPQ examinations comprised the study population. The mean age was 55.3 ± 14.8 years with a body mass index of 30.3 ± 7.6 kg/m, most women were parous (90%), 40% were Hispanic, and 33% had undergone prior hysterectomy for indications exclusive of POP. Women with any prior prolapse repair were excluded, 6.5% had a prior incontinence procedure. Perineal body measurements were slightly larger for stage 2 POP, but overall did not vary across other prolapse stages (all P > 0.05). In contrast, GH measurements increased through stage 3 POP, GH measurements decreased for stage 4 POP.

Conclusions: Mean PB measurements did not demonstrate large changes over prolapse stage, whereas GH measurements increased through stage 3 POP. Genital hiatus serves as an important marker for underlying pelvic muscle damage.