Anatomic Criterion for Clinically Relevant Apical Prolapse in Urogynecology Populations.

Importance: Despite recognition of the critical role of the apex in vaginal support, there is no consensus on the anatomic criteria for clinically relevant apical prolapse.

Objective: The aim of this study was to define an optimal anatomic criterion for clinically relevant apical prolapse.

Study Design: This retrospective cohort study included 3,690 patients who had visited a tertiary hospital for ambulatory urogynecologic care. Vaginal bulge symptom was defined as a response of "somewhat," "moderately," or "quite a bit" to Question 3 on the Pelvic Floor Distress Inventory-20. Receiver operating characteristic curves were generated for a vaginal bulge symptom and apical support (Pelvic Organ Prolapse Quantification point C and C/total vaginal length [TVL]).

Results: Both point C and the C-to-TVL ratio (C/TVL) had excellent performance for predicting vaginal bulge symptoms (area under the curve, 0.917 and 0.927, respectively). The optimal cutoffs were -3.0 for C and -0.50 for C/TVL. When we analyzed the data set according to the TVL, there was a significant difference in the cutoffs for C, whereas those for C/TVL had little difference. There was no difference in the cutoffs of C and C/TVL according to hysterectomy status.

Conclusions: The C/TVL is more appropriate than point C as a measure to define an anatomic criterion for clinically relevant apical prolapse. Descent of the vaginal apex beyond the halfway point of the vagina could be considered as an anatomic threshold for clinically relevant apical prolapse. This finding needs to be validated in nonurogynecology populations.