Hello. Thank you for your post/
I'm not sure your bladder has shrunk in the way you might think. Maybe the bladder's capacity to hold urine has. You should ask your doctor to explain what he or she means. An overactive bladder causes an uncontrollable and unstoppable urge to pass urine and the frequent need to urinate both during the daytime and night, even though the bladder may only contain a small amount of urine. It is sometimes referred to as small bladder syndrome.