What can happen if you hold your urine in for too long?

Bladder distends.: Holding the urine for long periods of time can distend the bladder, stretching out the muscle that allows the bladder to expel urine. If this stretching is great and often enough, the muscle slowly remodels itself, weakening over time. A weak bladder can show hesitancy. As voiding habits improve some of the effects are reversible, but any permanent damage from longstanding distention is not.