Women who underwent POP surgery are at risk of developing urinary incontinence (UI). This worsens the quality of life of women and their satisfaction with the procedures. However, a combined procedure of POP and anti-incontinence surgeries may be associated to some complications and increases the costs of the surgery.
The aims of the study are:
1. To know the incidence of persistent, de novo and cure of UI in patients undergoing vaginal POP surgery.
2. To describe the predictive factors for the onset of UI and develop a predictive model for the occurrence of SUI one year after surgery.

This is a prospective multicentre descriptive study. The Ethics Committee of all the 14 participating centres approved the research protocol. 
All patients with symptomatic POP, eligible for vaginal surgical treatment were included. The only exclusion criterion was the inability to provide the consent to participate in the study.
Preoperative and postoperative evaluation included an interview on symptoms of urinary incontinence, physical examination with a cough stress test and used the Sandvik and ICIQ-SF questionnaires. Postoperative follow-up was scheduled 12 months after surgery. The primary outcome was the presence of SUI or UUI 1-year after surgery.
Univariate and multivariate analyses were performed with baseline variables by means of logistic regression. A two-tailed p value < 0.05 was considered to indicate statistical significance. Finally, predictive models for SUI were developed using an all-possible-models analysis approach and evaluated according to Mallows’ Cp criterion.

Our cohort included 659 women, of whom 611 were analyzable. Baseline and surgical characteristics are detailed in Table 1.
The prevalence of SUI one year after surgery was 13.3%. The incidence of de novo SUI was 8.3%. When SUI occurred, its severity was mild to moderate (median Sandvik test = 4; ICIQ-SF = 9), requiring subsequent anti-incontinence surgery in only 4 cases (0.6%). Notably, 70.1% of patients with preoperative SUI were cured with POP surgery alone. Variables associated with the presence of SUI at one year included preoperative SUI, prior POP surgery, family history of UI, and Latin ethnicity (Table 2).
Regarding urge urinary incontinence (UUI), its prevalence at one year was 21.1%. The incidence of de novo UUI was 8.9%, and was higher in patients who received a concomitant anti-incontinence sling (30.0% vs. 8.3%; p = 0.17). Its average severity was moderate (median Sandvik test = 4; ICIQ-SF = 11). Additionally, POP surgery resolved pre-existing UUI in 57.7% of cases. Several baseline characteristics were associated with UUI in univariable analysis, although only age and preoperative UUI remained significant in multivariable analysis (Table 2).
The best-fitting predicting model includes preoperative SUI, prior POP surgery, and family history of UI. This model achieved an area under the curve of 0.752.

In our population, the incidence SUI after POP surgery is very low. The need for secondary SUI surgery is uncommon. Furthermore, pre-existing UI can be resolved in a high percentage of cases with isolated vaginal POP surgery.
Risk factors for the development of SUI and UUI differ, representing two distinct scenarios. On one hand, SUI appears to be strongly influenced by genetic characteristics, with family history and certain racial factors playing a significant role. On the other hand, UUI seems to represent a condition more influenced by patients’ systemic characteristics, although genetic factors may also play a role.
Regarding the development of predictive models, given the low incidence of postoperative SUI, these models are expected to have low clinical performance.

The rate of UI after vaginal POP surgery is low and few women require further surgery for SUI. Both SUI and UUI could be cured after only POP surgery.