Urodynamics Study

A UD study is an evaluative study done to examine how well the lower urinary tract (bladder, urethra, and sphincters) is functioning. It is an important step in the diagnostic workup for patients who experience urinary symptoms such as urinary incontinence (leakage), urgency, frequency, or retention. It is also beneficial for patients with a pelvic organ prolapse, bladder pain, or a history of recurrent UTIs. This bladder study provides several useful pieces of information about bladder capacity, muscle activity, and This study will take anywhere from around 45 minutes to 60 minutes.

How to prep for the procedure:

  1. Discontinue any bladder medications you take at least one week prior to the study
  2. Take the prophylactic antibiotic pill 1 hour prior to the study
  3. Come to your appointment with a full bladder

What does the study look like?

  1. You will empty your bladder on a special commode.
  2. A small catheter will be placed in your bladder and another catheter into the vagina.
  3. Tubes will be attached to the computer and these will be used to start filling your bladder with sterile water.
  4. You will be asked about sensations you are having while your bladder is filling.
  5. You will empty your bladder again.

What is the study assessing?




  • Uroflowmetry: When you void on the commode, the volume and flow rate of urine as the bladder empties will be calculated. This test helps to determine the efficiency with which the bladder empties.
  • Post‐void residual urine: A catheter will be inserted into the bladder to determine how much residual urine there is in the bladder. There will usually be some urine remaining in the bladder after voiding. This is only concerning if the amount of remaining urine is high.
  • Q‐tip test: A test to measure the mobility or movement of the urethra during straining.
  • Cystometry: The pressure catheter will be used to gradually fill your bladder while you will be asked to hold the fluid as long as you can. A vaginal catheter will be placed to record the pressure as well. You will be asked how your bladder feels, and when you feel
    the urge to urinate.
  • Leak‐Point Pressure: If you have contractions of the bladder which squeeze some water out, the cystometer will record the pressure at which the leak is occurring. You may be asked to hold your breath and bear down, to apply abdominal pressure to the bladder, to demonstrate the leak. This determines the ability of the sphincter muscle to hold the urine in the bladder.
  • Pressure-Flow Study: After the cystometrics, you will be asked to empty the bladder so that the catheter can measure the pressures while you urinate.
  • EMG (Electromyogram): This test measures the activity of the pelvic muscles, using sensors placed on the skin near the anus.

What to expect after the procedure:

After the tests, you may have mild discomfort for a few hours. Drinking two 8 ounce glasses of water each hour for two hours should help. Warm baths or holding a warm, damp washcloth over the urethral opening may help to soothe any irritation.

You will be asked to schedule a follow up appointment to discuss the results of this study. At that follow-up, you may receive additional treatment recommendations to help create your unique treatment plan.
Please call the office if you develop any sign of infection including fever, chills, or severe pain.

Please call our office at 301-652-1231 to schedule an appointment for a urodynamics study.