Home > Infectious Disease > Causes of Urinary Tract Infections Get the Flash Player to see this player. Rate: (Click the stars to rate) Published on Aug 19, 2008 by MBoone, Views: 2164 Causes of Urinary Tract Infections - Martha B Boone, MD. Most urinary tract infections are caused by the bacteria E.Coli. Bacteria go from the rectum to the vagina, commonly aided by sexual intercourse. Then the bacteria tracts to the ureter and the bladder. The first sign is usually burning when you urinate. Cranberry juice can help prevent some of these infections. I assume the cranberry juice is for drinking. Could there be any benefit to putting some cranberry juice in THAT area before sex to help prevent an infection. fortythenewthirty 4.6 years ago