Risk factors in women
- Sexual activity, which pushes bacteria into the urethra. Sexual activity with the use of a diaphragm and spermicide raises the risk.
- Previous UTIs.
- Lack of estrogen, which allows bacteria that can cause UTIs to grow more easily in the vagina or urethra. Women who have gone through menopause are at increased risk for UTIs.
Risk factors in men
Things that increase a man's risk of UTIs include:
- Problems with the prostate gland . Men become increasingly prone to UTIs as they get older because of prostate problems, such as enlarged prostate (benign prostatic hyperplasia) and prostatitis.
- An uncircumcised penis.
- Anal intercourse.
- Unprotected sex with a woman who has a vaginal infection.
- HIV infection.
Risk factors in both women and men
Certain risk factors apply to both women and men. These include:
- Having a catheter in place. Bacteria can enter the catheter and start an infection. Most at risk are older adults who are in hospitals or who live in long-term care facilities.
- Kidney stones and other obstructions in the urinary tract. These may block the flow of urine, raising the risk of bacterial infection.
- Diabetes. People with diabetes are at greater risk for UTIs because their immune systems are weakened. Also, long-term high blood sugar can damage the kidneys' filtering system (diabetic nephropathy).
- Structural problems of the urinary tract. These may be present at birth or develop later in life.