Until recently, it was thought that the bladder—and therefore urine—is sterile, meaning that, in a healthy state, no bacteria live there. But a new study presented by researchers at the General Meeting of the American Society for Microbiology is changing how scientists view the urinary system.

Using an expanded culture technique able to detect bacteria that standard techniques do not, they found that urine from healthy women does, in fact, contain bacteria.

“Doctors have been trained to believe that urine is germ-free,” noted Linda Brubaker, MD, MS, one of the researchers. “These findings challenge that notion, so this research opens the door to exciting new possibilities for patient treatment.”

They found that the bacteria in urine of women with an overactive bladder (OAB) differs from that of healthy women.

“The presence of certain bacteria in women with overactive bladder may contribute to OAB symptoms,” noted lead investigator, Evann Hilt.

Could changing the balance of bacteria in the urinary system improve symptoms of overactive bladder? Scientists will next look at which bacteria are helpful and which are harmful, and whether certain bacteria trigger the development of overactive bladder as well as other urinary tract conditions. With this information, they will better be able to treat this condition. They may find that by altering the bacteria in the urinary system, they can improve symptoms of overactive bladder. There may one day be a probiotic specifically for this condition. I am sure there are many women out there crossing their legs and nodding, yes!

The results of this study are not surprising to me, since I have known for a while that probiotics can have a positive effect on urinary health. The mechanism of this benefit is not fully understood, but it seems to me that it must involve communication between bacteria within the urinary system. I will be interested to see how this research unfolds as scientists further explore the human microbiome. My hunch is that they will find bacteria in more areas of the body they previously thought did not contain microbes.