Stress urinary incontinence (SUI) is the involuntary loss of urine often caused by physical movement or activity, such as coughing, sneezing, running or heavy lifting. Stress urinary incontinence occurs when the muscles that support the bladder and urethra weaken. 50% of women suffer from unwanted bladder leakage and 46% of women with urinary incontinence say it negatively affects their sexual function.