Uroflowmetry is a test that measures the volume of urine excreted (released) from the body, the speed with which it was excreted, and how long the excretion took.

You will urinate in a special urinal or toilet equipped with a machine that has a measuring device.

You are asked to press a button shortly before you try to begin urination, and you may be asked to press the button again when you finish. This machine will create a report for your health care provider.

Your provider may ask you to temporarily discontinue medications that can alter test results.

Uroflowmetry is best preformed with a full bladder. Do not urinate for 2 hours prior to the test. Increase the volume of fluids you drink so you will have plenty of urine for the test.

Do not place any toilet tissue in the test machine.

The test involves normal urination, so you should not experience any discomfort.

This test is useful in evaluating the function of the urinary tract.

Normal values vary depending on age and sex:

• Age: 4 to 7
  • The average flow rate for both males and females is 10 mL/sec.
• Age: 8 to 13
  • The average flow rate for males is 12 mL/sec.
  • The average flow rate for females is 15 mL/sec.
• Age: 14 to 45
  • The average flow rate for males is 21 mL/sec.
  • The average flow rate for females is 18 mL/sec.
• Age: 46 to 65
  • The average flow rate for males is 12 mL/sec.
  • The average flow rate for females is 15 mL/sec.
• Age: 66 to 80
  • The average flow rate for males is 9 mL/sec.
  • The average flow rate for females is 10 mL/sec.

Results must be understood as they relate to the patient’s complaints and physical exam. A result that may need treatment in one patient may require no treatment in another patient.

Several circular muscles normally regulate urine flow, and if any of these muscles becomes weak or stop working, an increase in urine flow or urinary incontinence may result.

If there is a bladder outlet obstruction or if the bladder muscle is weak, a decrease in urine flow may result.

Any abnormal results should be discussed with you and explained by your health care provider.

There are no risks associated with this test.