Urogynecology (Phila). 2025 Feb 26. doi: 10.1097/SPV.0000000000001660.Online ahead of print.

Uduak U Andy ¹, Benjamin Carper ², Halina Zyczynski ³, Abhishek Sripad ⁴, Keisha Y Dyer ⁵, Joseph Schaffer ⁶, Donna Mazloomdoost ⁷, Marie G Gantz ²; NICHD Pelvic Floor Disorders Network

Author information

¹From the Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia, PA.

²Social, Statistical, and Environmental Sciences, RTI International, Research Triangle Park, NC.

³Department of Obstetrics, Gynecology and Reproductive Sciences, University of Pittsburgh Medical Center, Pittsburgh, PA.

⁴Department of Obstetrics and Gynecology, Alpert Medical School of Brown University, Providence, RI.

⁵Department of Obstetrics and Gynecology Kaiser Permanente, San Diego, CA.

⁶Department of Obstetrics and Gynecology, University of Texas Southwestern Medical Center, Dallas, TX.

⁷The Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD.

Abstract

Objective: This study aimed to determine the effect of a run-in period on fecal incontinence (FI) symptom severity.

Study design: This study conducted a planned secondary analysis of the run-in period to a study evaluating the effect of 12-week treatment with percutaneous tibial nerve stimulation versus sham in reducing FI severity in women. All participants completed a 4-week run-in period designed to exclude from randomization women whose symptoms reduced below the eligibility threshold after receiving education on FI and completing bowel diaries. Change in St Mark's (Vaizey) score and weekly FI episodes during the run-in period (week 1 vs week 4) was assessed.

Results: One hundred and eighty-five women completed the run-in period. The mean St Mark's (Vaizey) score was 17.8 ± 2.6 and 16.9 ± 3.5 at week 1 and week 4, respectively. There was no significant change in the St Mark's (Vaizey) score from week 1 to week 4 (mean change, -0.93 [95% CI, -1.56 to -0.31]). The average number of FI episodes per week did not change significantly between week 1 and week 4, nor did other bowel diary measures. Only 11 (6%) women became ineligible for the trial following the run-in period, all of whom had baseline St Mark's (Vaizey) scores of 18 or lower.

Conclusions: Completion of a bowel diary and receiving education on FI during the 4-week run-in period did not significantly affect symptom severity in women with FI. Only 6% of women became ineligible for participation following the run-in period, suggesting that, in a refractory population, a run-in period may have minimal effect.