Perineal tear classification is a system used to quantify the severity of trauma to the perineum during vaginal childbirth. Delivery may lead to overstretching of the vagina, causing tears in the perineal tissue between the vagina and rectum. Lacerations are classified into four categories:

• First degree tear: laceration is limited to the fourchette and superficial perineal skin or vaginal mucosa
• Second degree tear: laceration extends beyond fourchette, perineal skin and vaginal mucosa to perineal muscles and fascia, but not the anal sphincter
• Third degree tear: fourchette, perineal skin, vaginal mucosa, muscles, and anal sphincter are torn
• Fourth degree tear: fourchette, perineal skin, vaginal mucosa, muscles, anal sphincter, and rectal mucosa are torn