Bacteria in women can enter the bladder more quickly, women tend to get urinary tract infections more often than men. In women, the urethra (opening to your urinary tract) is shorter than in men, so bacteria can travel a shorter distance. In females, the urethra is found near the rectum. Rectum bacteria can migrate up the urethra easily and cause infections. If you clean from back to front (instead of front to back) following a bowel movement, rectum bacteria would be more likely to get into the urethra. As bacteria can be forced into the urethra, having sex can also cause urinary tract infections in women. Since diaphragms press against the urethra and make it more difficult to fully empty your bladder, using a diaphragm can lead to infections. The urine that remains in the bladder is more likely to cause infections and produce bacteria.
Changes in bacteria in the vagina can be responsible for frequent urinary tract infections. Alterations of vaginal bacteria can be caused by antibacterial vaginal douches, spermicides and some oral antibiotics. If possible, avoid using these products. Changes in vaginal bacteria that raise the risk of urinary tract infection can also be caused by menopause. Typically, taking estrogen corrects this problem, but it may not be for everybody.