When the bladder is begging for relief, ignoring one's bodily cues for the sake of productivity or lounging around is common.
How many times have you decided that you just need to get through a meeting or the last few hours of a road trip first, or that you really don't want to miss a second of the movie you just paid $25 to see?
Holding your pee in every so often generally can be harmless, but there are some cases in which the behaviour can pose threats to your health, especially if it's a regular, learned behaviour, said Dr Jason Kim, clinical associate professor of urology at the Renaissance School of Medicine at Stony Brook University on Long Island, New York.
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These risks stem from the reasons and the way we urinate in the first place.
"There's a complex neurological system that controls urination," added Kim, who is also director of the university's Women's Pelvic Health and Continence Center.
"Your kidneys make urine, and then (it's) funnelled down two tubes called ureters to the bladder. I'd say normal bladder capacity is about 400 to 600 (cubic centimetres)."
Once the bladder is about half full, nerve receptors tell the brain it's time to pee, and the brain tells your bladder to hold it until a socially acceptable time to urinate, Kim said.
That's when the brain will send signals that relax the urethral sphincter muscle and make the bladder muscles contract to squeeze urine out, Kim said.
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"We were built this way because if we just peed as we were walking along, let's say, the road, our predators would smell us," said Dr David Shusterman, board-certified urologist at NY Urology in New York City.
"Urine has concentrated toxins in it, which is why your body is trying to get rid of it — and so what ends up happening is you want to hold the toxins in because they have a smell to them, and you want to be able to excrete the toxins in a time where you're more protected."
Based on this science, here's what else you need to know about the risks of holding your pee.
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The possible cons of postponing the piddle
Holding pee in can increase your risk of getting a urinary tract infection, or UTI, which results from bacteria entering the urinary tract.
While peeing ideally would flush out any new invaders, retaining urine can "create a breeding ground for bacteria," Dr Jamin Brahmbhatt, a urologist at Orlando Health and a CNN contributor, said via email.
This is why people, especially those with female anatomy, are told to pee after sex since the friction of sexual activity can push bacteria into the urethra.
If left untreated, a UTI can ascend into the kidneys and result in kidney infection pyelonephritis, Kim said. If that infection, too, goes unchecked, there can be a bloodstream infection or urosepsis — sepsis from a urinary source.
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Over time, holding pee in too often can strain, and thus weaken, your bladder muscles, which then cannot generate enough force to empty the urine, experts said.
This makes "it harder to empty completely when you finally go," Brahmbhatt said.
"When that happens, you can enter a vicious cycle — more leftover urine means more risk for infections."
Consistently overriding bodily signals can make them start to be less evident or not work, experts said.
"We see a lot of this happening in nurses and teachers," Kim said.
"They don't go to the bathroom at all throughout the day when they're on shift or in the classroom."
If you can't pee, don't wait to see if something changes — seek evaluation from a doctor. Available treatments include self-administered intermittent catheterisation, long-term catheterisation or sacral neuromodulation — a bladder pacemaker that can sometimes "restore the ability for the bladder muscle to squeeze normally," Kim said.
In more extreme cases, experts said, holding pee can cause urine to back up into the kidneys, which can lead to infections, kidney damage or hydronephrosis. The latter is a condition in which the kidneys swell and stretch from the buildup. Not emptying your bladder enough can also cause abdominal pain, cramping or bladder stones.
How risky is holding your pee?
Heeding your body's cues as quickly as you can is always best, experts said, especially since you never know when your urethra has encountered bacteria that could lead to a UTI.
For the average healthy person, however, holding your pee for up to a few hours a few times a week isn't likely to cause harm, experts said. But if regularly ignoring your urge to pee goes on for weeks or longer, you're putting your bladder and kidneys under unnecessary strain.
There are some people for whom delaying urinating can be more dangerous than usual, necessitating more diligence.
That applies to those who may not be able to fight infections as well, including older people who may also experience a reduced capacity to urinate normally since ageing can be accompanied by growing prostates (for men) and tightening urethras (for women), Shusterman said.
Those with neurogenic bladder or kidney disorders are also at greater risk of harm from holding their pee.
People who are pregnant should also take extra care to honor the urge to pee, as they're already at greater risk for UTIs due to the increased weight and pressure of the uterus on the bladder, which can block urine from emptying, Shusterman said.
If you smoke or work around toxins such as gasoline, you're at higher risk of developing bladder cancer, Shusterman added, so peeing frequently is important for you, too.
If you're holding your pee because you've noticed you're running to the toilet unusually often, that could be a sign of overactive bladder syndrome, diabetes or a UTI, experts said. In this case, see a urologist who can help you get to the bottom of things and start you on some bladder training exercises.
If you're uncomfortable with public bathrooms, "I get it," Brahmbhatt said via email. "But it's better to go when your body needs to than to hold it in. Carry some disinfecting wipes or a portable seat cover if it makes you more comfortable. Your bladder and future self will thank you!"
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