Trans‑obturator tape (TOT) is an approved treatment for female stress urinary incontinence (SUI), but its efficacy in obese patients remains debated. The relationship between abdominal leak point pressure (ALPP) and body mass index (BMI) is not well understood. This study objective is to evaluate the impact of BMI on outcomes of TOT and to investigate if ALPP interacts with BMI in predicting treatment success or failure.

A retrospective cohort of women who underwent TOT for pure SUI or mixed incontinence (2017‑2024). Patients were divided by BMI: normal (<25), overweight (25‑29.9), obese (30‑34.9), and morbidly obese (≥35). The primary outcome was dry rate (Totally dry/Dry most of the time/failed). Secondary outcomes included de novo urgency and voiding dysfunction (Qmax<15 mL/s, PVR>100 mL, or use of self-catheterization). Multivariate logistic regression to identify predictors of failure was used, especially the ALPP‑BMI interaction. Pearson correlation tested the relationship between BMI and ALPP.

We found 59 patients. We found a higher prevalence of diabetes in morbidly obese patients (25% vs. 0‑12.5%, p=0.04). Overall, 52.5% were totally dry, 40.7% were dry most of the time, and 6.8% failed. Failure rates were 15% in morbidly obese, 6.2% in obese, and 0% in normal/overweight groups (p=0.048). Lower ALPP was a a significant independent predictor of failure (adjusted OR per 1 cmH₂O 0.95, 95% CI 0.91‑0.99, p=0.03), whereas morbid obesity showed only a trend towards worse outcome (OR 6.21, p=0.14). The ALPP and BMI correlation was not significant (p=0.38), indicating that the predictive value of ALPP does not change with BMI. BMI and ALPP were weakly negatively correlated (r=‑0.22, p=0.09). De novo urgency occurred in 23.7%, with a non‑significant higher rate in morbidly obese patients (35% vs. 14‑19%, p=0.38). Voiding dysfunction was foundt in 15.3% and was associated with lower success rates (66.7% vs. 94.0%, p=0.03). Multivariate analysis confirmed that only lower ALPP (<60 cmH₂O) independently predicted failure after adjusting for age, BMI, and parity.

Low preoperative ALPP independently predicts TOT failure, morbid obesity does not. TOT remains highly effective (>90% success) across all BMI groups. Patient selection should prioritize urodynamic ALPP over BMI, and obese patients need counseling about de novo urgency risk.

TOT is highly effective (>90% Totaly dry or dry most of the time) even in obese and morbidly obese women. Morbid obesity does not independently increase failure risk. Preoperative low ALPP (<60 cmH₂O) predicted failure regardless of BMI. Increased BMI does not correlate with higher ALPP but, there is a trend toward lower ALPP in more obese women. Patient selection for TOT should urodynamic ALPP rather than BMI alone. Morbidly obese patients should be counseled about a slightly higher risk of de novo urgency and the importance of baseline urodynamic ALPP.