An average adult bladder can hold up to about 2 cups (about half a liter) of urine before your brain starts telling you it's time to relieve yourself. Could waiting to pee actually cause your bladder to burst?
The answer is a qualified yes. Trauma, surgery or radiation can cause a bladder to become injured, retain urine and burst. Another newly documented danger is binge drinking. A report in the British Medical Journal found that alcohol-induced bladder rupture has sent a number of women to hospital emergency rooms.
Physicians found that men and women were equally at risk for bladder ruptures, but that more women were now drinking large quantities of alcohol. In the cases of three women admitted to a hospital in England, they complained of lower abdominal pain after drinking excessive amounts of alcohol and doctors discovered that women's bladders had burst. Alcohol increases urine output, while simultaneously dulling the urge to empty the bladder.
These effects, coupled with mild trauma, such as a fall, greatly increase the risk of rupture. If the bladder bursts it releases urine into the abdominal cavity which results in lower abdominal pain. The treatment involves a procedure in which a catheter is inserted via the urethra to drain the urine. There's usually a surgical procedure required to repair the bladder and clean the abdominal cavity.
Most people don't need to worry about holding their pee until their bladder bursts, though. The more likely scenario is that you'll pee your pants long before your bladder ruptures. Draining your bladder frequently and completely is good for your health because it helps avoid infections brought on by bacteria buildup.
A full bladder can be agony and you can even experience diminished focus and cognitive abilities plus a lot of squirming. Nobody in the pee world business has been able to conclusively identify what causes this behavior, but there are a few theories.
Bouncing up and down while clenching your legs together could perhaps both lighten the load on the bladder sphincter and help you feel a little more in control. It's probably not very effective, but it might fool your brain into thinking things aren't so bad. Another idea is that when we're in a tough psychological situation, we look for solace in anything outside of the pain we're in. Squirming can help temporarily override the discomfort.
The most likely theory is a psychological one...rhythmic displacement behavior. When faced with conflict, it's in our nature to move in a rhythmic way. When we're faced with two strong but contradictory urges, anxiety can cause us to perform little repetitive movements like nail biting, head scratching and pee-pee dancing. We experience this conflict in the form of the urge to pee right now and the necessity of waiting.