A perineal tear is an injury to the skin, muscle, and other soft tissues located between the vaginal opening and the anus, an area known as the perineum. This injury is a common outcome of vaginal childbirth, but the severity varies widely. Understanding the nature of these tears and implementing proven preventative strategies can significantly reduce the risk of a severe injury.
Understanding Tear Severity and Risk
Perineal tears are classified into four degrees to describe the extent of the tissue damage. First-degree tears are the least severe, involving only the skin and superficial tissue, often healing quickly without stitches. The most common injury is a second-degree tear, which extends deeper into the muscle of the perineum and typically requires suturing for repair.
More serious injuries are classified as third- and fourth-degree tears, collectively known as obstetric anal sphincter injuries (OASIs). A third-degree tear involves the anal sphincter muscle, which controls bowel function. The most extensive injury, a fourth-degree tear, extends completely through the anal sphincter and into the rectal lining.
Several factors increase the likelihood of experiencing a tear, particularly a severe one. Individuals having their first vaginal delivery face a higher risk. The size of the baby is also a factor, with fetal weight exceeding 4,000 grams or a large head circumference increasing the strain on the tissues. Instrumental delivery using forceps or a vacuum extractor, as well as a prolonged second stage of labor, are recognized risk factors for more extensive perineal trauma.
Preparation Techniques Before Labor
Preparing the perineum in the weeks leading up to labor can help improve the tissue’s capacity to stretch. Perineal massage is a well-established technique that can be started around the 34th or 35th week of pregnancy. This regular practice is particularly effective for individuals expecting their first vaginal birth, as it has been shown to reduce the risk of needing an episiotomy and the chance of a severe tear.
To perform the massage, use a natural, food-grade oil, such as almond, olive, or coconut oil, for lubrication. The individual or a partner inserts a thumb or two fingers a few centimeters inside the vagina and applies gentle, sustained pressure downward toward the anus and outward to the sides. This pressure should be held for one to two minutes, stretching the perineal tissues to mimic the sensation of crowning.
The massage is continued by moving the fingers in a slow, U-shaped motion along the lower vaginal wall for a few minutes. Repeating this process daily or every other day for five to ten minutes helps the tissue become more pliable and elastic. Maintaining good overall tissue health through adequate hydration and a diet rich in healthy fats and collagen-supporting nutrients also supports the perineum’s resilience.
Strategies During Pushing and Delivery
The actions taken during the second stage of labor directly influence the risk of perineal tearing. Birthing positions that minimize tension on the perineum are recommended over lying flat on the back (lithotomy position). Positions like side-lying (lateral) or hands-and-knees allow for greater pelvic mobility and reduce direct downward pressure on the perineal tissues. The side-lying position is often considered protective and is an option even with an epidural.
Providers use specific techniques to support the perineum as the baby is crowning. Applying a warm, moist compress to the perineal area during the pushing phase has been shown to increase tissue elasticity and reduce the incidence of severe tears. Providers also utilize “hands-on” perineal support, gently supporting the perineum while controlling the speed of the baby’s head as it emerges. This controlled guidance allows tissues to stretch gradually, preventing rapid expulsion that can lead to trauma.
The method and timing of pushing are significant factors in reducing injury. “Laboring down,” or passive descent, involves delaying active, forceful pushing until the individual feels a strong, involuntary urge, even after full cervical dilation. This allows the uterus and gravity to naturally move the baby lower into the birth canal, conserving energy and encouraging a slower descent.
The style of pushing should favor spontaneous, or physiological, effort rather than directed, or coached, pushing. Spontaneous pushing involves following the body’s natural urges to bear down, which usually means shorter pushes without prolonged breath-holding. Directed pushing, which often involves a forceful Valsalva maneuver (holding the breath and pushing hard), increases pressure on the pelvic floor and leads to a less controlled crowning. Finally, a surgical incision called an episiotomy is generally avoided as a routine preventative measure, as it can increase the risk of a more severe tear than a spontaneous laceration.