Peeing at 4 a.m. and then peeing at 8 a.m. is not considered morning urine. Because in the clinical morning urine is generally required to be retained in the bladder for about 6 to 8 hours, due to its various components are more concentrated, easy to compare, and not affected by diet, so the test results are more accurate. Check morning urine is commonly used in routine urine examination to check the urine cells and tubular, especially a variety of formed components such as blood cells, tubular, epithelial cells, crystals, tumor cells, etc., as well as urine sugar, urine protein and other items of the determination, but need to pay attention to the morning urine should be stored in the bladder for 6 to 8 hours to check the results are more accurate. Urine specimens should be sent to the laboratory for testing immediately after retention, generally from specimen collection to the completion of the test, summer should not exceed 1 hour, winter should not exceed 2 hours. If the specimen cannot be sent for testing immediately, it should be preserved with preservatives and kept refrigerated. The container for specimen collection should be clean and dry, and female patients should avoid menstruation to prevent vaginal secretions or menstrual blood from mixing.