Updated

Baby boys who are uncircumcised have an increased risk of urinary tract infection - whether their foreskin is "tight" or not, a study published Monday finds.

Doctors have long known that baby boys who remain uncircumcised are more likely to get a urinary tract infection (UTI) than circumcised babies are.

But their absolute risk is still low, said Dr. Alexander Sasha Dubrovsky, the lead researcher on the new study.

According to the American Academy of Pediatrics (AAP), an uncircumcised boy has about a one in 100 chance of developing a UTI in his first year of life. The risk for a circumcised baby is one in 1,000.

But doctors have wondered whether only certain uncircumcised boys might be at increased risk. Namely, those with a "tight foreskin" and a hard-to-see urethral opening, explained Dubrovsky, of Montreal Children's Hospital and McGill University in Quebec, Canada.

In theory, that could be the case, because the tighter foreskin may harbor more bacteria that could lead to a UTI.

So Dubrovsky's team looked at the question by studying 393 baby boys who were sent to their hospital's ER for UTI testing.

Of those babies, 309 were uncircumcised - about what the researchers expected since being uncircumcised is a known risk factor for infant UTIs, so those boys were more likely to be sent for testing.

And the uncircumcised babies were indeed more likely to test positive for an infection: one-quarter did, versus five percent of the circumcised babies who got tested.

But among the uncircumcised babies, there was no evidence that foreskin "tightness" mattered in their risk for infection. They had a higher UTI risk regardless of whether the urethral opening was clearly visible or hard to see.

The findings are published online in the Canadian Medical Association Journal.

In babies, UTIs are tough to recognize because they typically cause only vague symptoms, like a low fever or fussiness. Those same symptoms crop up with colds or other common childhood ills, and most babies with such symptoms do not have a UTI, Dubrovsky said.

So doctors try to figure out which babies have an increased chance of a UTI and test them - instead of testing every infant with possible symptoms.

That's largely because in order to get a clean urine sample from a baby, doctors usually have to use a catheter.

"It's not a comfortable procedure," Dubrovsky said. "So we want to minimize the number we do."

Circumcision is one of the factors doctors consider in deciding to test baby boys for a UTI. That is, their suspicion of a UTI is higher when a boy is uncircumcised.

And based on the current findings, that shouldn't change, the researchers say.

UTIs are usually not serious and can be easily treated with antibiotics. In some young children, though, repeat UTIs may be a sign of an abnormality in the urinary tract. And untreated infections could scar the kidneys.

Dubrovsky stressed that the study was not set up to inform the debate over circumcision.

Right now, the AAP does not recommend routine circumcision. There are some possible health benefits: besides the somewhat lower risk of UTI in infancy, circumcised boys may have a slightly lower risk of sexually transmitted diseases, including HIV, later in life. They also seem to have a lower risk of penile cancer, but that's a rare disease.

The AAP does not consider those possible benefits strong enough to warrant routinely circumcising boys.

"Our study doesn't answer any questions on the potential benefits of routine circumcision," Dubrovsky said.

He suggested that parents talk with their doctors about the possible pros and cons of circumcision, then decide for themselves.