Contributed by- Healthians Team

What is the urine specific gravity test?

The body produces urine as a way to get rid of waste and additional water that it doesn’t require and the role of the kidney is to concentrate the urine, such that waste molecules can be excreted with minimal loss of water and nutrients. The concentration of the excreted molecules determines the urine’s specific gravity. 

Urine specific gravity test is used to compare the density of urine to the density of water. More concentrated urine means that the kidneys are not functioning properly or you are not drinking enough water. Less concentrated urine means that you have a rare condition called diabetes insipidus, which causes thirst and the excretion of large amounts of diluted urine.

Who should get a urine specific gravity test?

The kidneys excrete extra water and minerals from the body in the form of urine. When the body needs more water, the kidneys retain fluid.

A doctor will use a urine specific gravity test if they suspect that a person is dehydrated or has impaired kidney function, or has a condition that can alter the body’s fluid status, such as diabetes insipidus.

Why is a urine specific gravity test needed?

The urine specific gravity test is a quick way for your doctor to tell if your kidneys are working well or trying to compensate for some abnormality.

Specific gravity testing is useful if your doctor thinks you have any of the following conditions:

  • dehydration or overhydration
  • heart failure
  • diabetes insipidus
  • kidney failure
  • kidney infection
  • urinary tract infection
  • Low or elevated sodium levels

What does urine specific gravity test results mean?

Your doctor will use the results from your urine specific gravity test, along with other urinalysis results, for proper diagnosis. Urine specific gravity measures your urine’s overall concentration than looking at the colour of your urine alone.

Your doctor will look at the ratio of the density of your urine to the density of water. To put it another way, the specific density of water would be 1.000. Ideally, urine specific gravity results will fall between 1.002 and 1.030 if your kidneys are working normally.

Specific gravity results above 1.010 can indicate mild dehydration. The higher the number, the more dehydrated you may be.

High urine specific gravity can indicate that you have extra substances in your urine, such as:

  • glucose
  • protein
  • bilirubin
  • red blood cells
  • white blood cells
  • crystals
  • bacteria

A person may need to stop taking certain medications before the test, particularly those that contain sucrose. Apart from it, no special preparations needed for the test.

How is the urine specific gravity test done?

A person must clean the urethral area before collecting the urine sample because the skin bacteria can get contaminated with the sample. For the test, your healthcare provider will ask you to collect a sample of your urine. You will be provided with a collection container. Besides, special instructions called the ‘clean catch method’ will also be shared with you to make sure that the sample you collect is sterile. Make sure that you collect the sample mid-stream and at least collect 30 to 60 ml. 

After you provide a urine sample, the lab technician marks on the container and sends your urine sample to a lab for the correct diagnosis.

Take the urine specific gravity test now