Vaginal discharge in a 14 year old can be due to a variety of reasons. If her GP is unable to determine the cause of her discharge, then a referral to a gynecologist is warranted. A physical exam is needed to evaluate her anatomy. In addition, the discharge should be evaluated to determine its composition (blood, mucous, pus, etc.). Lastly, if a physical exam and basic laboratory/gynecologic tests fails to determine the cause or nature of discharge, then additional testing such as ultrasound or CT scan may be needed.