A clinical trial will be conducted at the Clínica Universitaria de Navarra to treat urinary incontinence by injecting myoblasts into the urinary tract. The trial will be conducted with 15 women with urinary incontinence. Incontinence is largely due to the loss of sphincter muscle mass in adult women. According to the Navarran researchers, in the area of the urinary sphincter can be cured by injecting the muscle cells themselves (myoblasts). This increases this muscle and its contractility, decreasing incontinence.