Prophylactic concomitant midurethral slings (MUS) at the time of pelvic organ prolapse (POP) repair aim to prevent de novo stress urinary incontinence (SUI). Alternatively, a staged approach reduces unneeded procedures and adverse events associated with concomitant MUS [1].  Less is known about outcomes of a staged strategy in women with preoperative SUI. Our goal was to determine the proportion of women who have resolution of preoperative SUI after POP repair without a concomitant MUS. We also assessed the frequency of staged MUS procedures and factors associated with staged MUS.

We performed a retrospective, observational cohort study of women who underwent uterosacral ligament suspension or minimally invasive sacrocolpopexy by 7 FPRMS physicians in an academic medical center from 2009-2015. We included women who had both subjective SUI (defined as patient reported symptoms) and objective SUI (diagnosed by simple cystometry or multichannel urodynamics) preoperatively. We excluded cases with concomitant incontinence procedures. Our primary outcome was the proportion of women who had resolution of SUI after POP repair without a concomitant MUS.  Secondary outcomes included the frequency and timing of staged MUS as well as factors associated with staged MUS. Data were assessed using Mann-Whitney U for continuous and Chi-Square for categorical variables.

Our cohort consisted of 93 women who were predominantly Caucasian (97.8%) and multiparous (3, IQR 2-3) with mean age of 59.5 ± 8.9 years and BMI of 28.7 ± 4.7 kg/m2.  Most had stage III POP (59.1%). SUI was diagnosed by cystometry in 66.7% and by urodynamics in 33.3%.  The majority (83.9%) completed the SUI bother question on the Urogenital Distress Inventory (UDI-6) preoperatively (Figure 1). Mean follow-up was 16.9 months (range 0.48-82.2 months). 

Postoperatively, 31.2% (n=29) reported resolution of SUI while 68.8% (n=64) reported persistent SUI.  Among the 93 patients over the study period, 50.5% (n=47) were treated for postoperative SUI: 11.8% (n=11) with pelvic floor physical therapy, 2.2% (n=2) with periurethral bulking, and 36.6% (n=34) with a MUS. Seventeen patients (18.2%) reported SUI but did not receive treatment.

Among the staged MUS after POP repair, 79.4% (n=27) were placed within the first 12 months, 14.7% (n=5) between 12-24 months, and 5.9% (n=2) more than 24 months after the initial surgery. The median time to MUS placement was 5.5 months (IQR 4.2-9.9 months). Univariable analyses did not identify any patient factors associated with staged MUS (p>0.05).  There was no difference in preoperative SUI bother between women who did and did not have a staged MUS (p=0.88, Figure 1).

Our findings demonstrate that almost one-third of women experienced resolution of their preoperative SUI after POP repair. Only 37% of women underwent a staged MUS over an average follow-up of 16.9 months.  When compared to a strategy of concomitant MUS, a staged approach to treatment of preexisting SUI would result in an almost two-thirds reduction in placement of MUS.

The median time to MUS placement after surgery was 5.5 months, which is reassuring that those who desired a staged MUS were able to undergo the procedure within a reasonable timeframe. However, for some women, placement of MUS extended beyond 1 year after the initial POP repair. Future studies assessing MUS placement after POP repair should follow patients beyond the 12-month follow up visit.  

Our analyses did not identify patient or clinical predictors of staged MUS placement, suggesting an area of further research. Study limitations include the absence of information on postoperative SUI bother and reasons for not pursuing a staged MUS.

Resolution of preoperative SUI occurs in up to 31% of women undergoing surgery for POP.  Only 37% of patients had a staged MUS placed over an average follow up of 16.9 months. In a patient population who would typically be offered a concomitant MUS, our data suggest that almost two-thirds of MUS could be avoided if a staged procedure is chosen.

Wei, J.T., et al., A midurethral sling to reduce incontinence after vaginal prolapse repair. N Engl J Med, 2012. 366(25): p. 2358-67.