Overactive Bladder

Overactive bladder occurs when abnormal nerves send signals to the bladder at the wrong time, causing its muscles to squeeze without warning. Voiding up to seven times a day is normal for many women, but women with overactive bladder may find that they must urinate even more frequently.
Specifically, the symptoms of overactive bladder include

urinary frequency – bothersome urination eight or more times a day or two or more times at night
urinary urgency – the sudden, strong need to urinate immediately
urge incontinence – leakage or gushing of urine that follows a sudden, strong urge
nocturia – awaking at night to urinate