It’s true that most women have heard the term Pap smear, and many have even experienced them firsthand, but is it always clear why this procedure is so important? Not everyone knows, suggests a profile in Blood and Milk, that aims to shine some light on the reasons for this potentially lifesaving test.

Pap smears test “for changes to cervical cells that may be pre-cancerous or even cancerous,” according to Sarah Twogood, an OB-GYN in Los Angeles, as well as HPV. The procedure involves gently moving a series of small swabs over the surface of the cervix and takes approximately 10-20 minutes.

The best way to prepare for your Pap test is to speak with your doctor about your uncertainties and anxieties, notes Twogood. “They can explain exactly what they are doing and talk you through the exam before doing it.”

Read more about the how, why, and when of Pap testing, as well as what different results can teach you here.