Birth tears occur when the opening of the vagina cannot stretch enough to allow the head of the baby to pass through. As more force is applied by the baby’s head, the skin eventually tears. Tears are categorised into four types:
First-degree: A minor tear to the opening of the vagina or perineum (between the vagina and the anus). These often do not require stitches and have no long term consequences.
Second-degree: The muscles of the perineum also become torn during birth.
Third-degree: The perineal muscles and the muscles around the anus become torn. Surgical suturing is usually required to repair third-degree tears.
Fourth-degree: The perineal muscles, the anal sphincter, and the soft tissue around the rectum are all torn, requiring surgery to repair.
What are the reasons for an episiotomy or serious birth tear?
An episiotomy is commonly required if the head of the baby is too large to pass through the opening of the vagina without causing a serious tear, or if the birth process needs to proceed more quickly, perhaps due to foetal distress.
Serious birth tear injuries can occur if:
- the vaginal opening is allowed to stretch too quickly without suitable intervention
- assisted birth, such as forceps or vacuum delivery, is used
- the shoulder of the baby becomes lodged behind the pubic bone
- labour is induced
- it is the mother’s first baby
- the baby is large
- labour is prolonged