Urinalysis

What is the test?

A urinalysis is a routine examination of the urine for cells, tiny structures, bacteria, and chemicals that suggest various illnesses. A urine culture attempts to grow large numbers of bacteria from a urine sample to diagnose a bacterial urine infection.

How do I prepare for the test?

For a regular urinalysis, you are asked to urinate briefly into a plastic cup. When urine is collected for a urine culture, you must provide a "clean catch" sample - one that is not contaminated by skin cells and skin bacteria. This is so the doctor can obtain a sample of urine from inside your bladder, where normally there should be no bacteria. In contrast, there are many bacteria on the skin of a penis or in a vagina. The trick (harder for a woman than a man) is to pee directly into a sterile container without having the stream of urine first touch your skin or the nonsterile tissues of the vagina.

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