When we want to urinate, a coordinated set of actions occurs: the bladder contracts to initiate the flow of urine, and the urethra and pelvic muscles must relax and open to allow the urine to flow out. When you sneeze, cough, or exercise, the increased abdominal pressure from these activities overwhelms the urethra, allowing urine to escape.
So, what goes awry when somebody has stress incontinence? Either the urethral sphincter muscle is too weak, or the urethra itself is floppy and not well-supported, which can result from childbirth or simply aging.
