Introduction: During sexual stimulation, some women report the discharge of a noticeable amount of fluid from the urethra, a phenomenon also called "squirting." To date, both the nature and the origin of squirting remain controversial.

Conclusions: The present data based on ultrasonographic bladder monitoring and biochemical analyses indicate that squirting is essentially the involuntary emission of urine during sexual activity, although a marginal contribution of prostatic secretions to the emitted fluid often exists.