Urine specific gravity test. Urine specific gravity is a laboratory test that shows the concentration of all chemical particles in the urine. After you provide a urine sample, it is tested right away. The health care provider uses a dipstick made with a color-sensitive pad. The color the dipstick changes to will tell the provider the specific gravity of your urine. The dipstick test gives only a rough result. For a more accurate result, your provider may send your urine sample to a lab. Your provider will ask you to temporarily stop taking any medicines that may affect the test results.