Risk factors

Urinary tract infections are common in women, and many women experience more than one infection during their lifetimes. Risk factors specific to women for UTIs include:

Female anatomy. A woman has a shorter urethra than a man does, which shortens the distance that bacteria must travel to reach the bladder.

Sexual activity. Sexually active women tend to have more UTIs than do women who aren't sexually active. Having a new sexual partner also increases your risk.

Certain types of birth control. Women who use diaphragms for birth control may be at higher risk, as well as women who use spermicidal agents.

Menopause. After menopause, a decline in circulating estrogen causes changes in the urinary tract that make you more vulnerable to infection.

Other risk factors for UTIs include:

Urinary tract abnormalities. Babies born with urinary tract abnormalities that don't allow urine to leave the body normally or cause urine to back up in the urethra have an increased risk of UTIs.

Blockages in the urinary tract. Kidney stones or an enlarged prostate can trap urine in the bladder and increase the risk of UTIs.

A suppressed immune system. Diabetes and other diseases that impair the immune system — the body's defense against germs — can increase the risk of UTIs.

Catheter use. People who can't urinate on their own and use a tube (catheter) to urinate have an increased risk of UTIs. This may include people who are hospitalized, people with neurological problems that make it difficult to control their ability to urinate and people who are paralyzed.

A recent urinary procedure. Urinary surgery or an exam of your urinary tract that involves medical instruments can both increase your risk of developing a urinary tract infection.