‘Prophylactic’ episiotomy is not preventive
Much debate has centered on optimal utilization of so-called prophylactic episiotomy. The intent of routine prophylactic episiotomy is to protect the pelvic floor, thus minimizing the risk of urinary incontinence and pelvic floor dysfunction. Data have suggested that absence of labor and cesarean delivery may protect against pelvic floor dysfunction; however, the role of episiotomy in preventing such dysfunction remains to be determined.
Cochrane Database review. This review1 found no differences in vaginal or perineal trauma, dyspareunia, or urinary incontinence between patients with and without episiotomy. Patients who had an episiotomy had less risk of anterior perineal trauma but an overall greater risk of posterior perineal trauma and other complications. The reviewers concluded that restrictive episiotomy utilization is preferable to routine utilization.
The reviewers selected a total of 6 randomized trials; these examined:
- restrictive versus routine use of episiotomy;
- restrictive versus mediolateral episiotomy;
- restrictive versus routine midline episiotomy; and
- midline versus mediolateral episiotomy.
Compared with routine use, restrictive episiotomy involved less posterior perineal trauma (relative risk [RR], 0.88; 95% confidence interval [CI], 0.84 to 0.920), less suturing (RR, 0.74; 95% CI, 0.71 to 0.77), and fewer healing complications (RR, 0.69; 95% CI, 0.56 to 0.85). Restrictive episiotomy was associated with more anterior perineal trauma (RR, 1.79; 95% CI, 1.55 to 2.07).
There was no difference in severe vaginal or perineal trauma (RR, 1.11; 95% CI, 0.83 to 1.50), dyspareunia (RR, 1.02; 95% CI, 0.90 to 1.16), urinary incontinence (RR 0.98; 95% CI, 0.79 to 1.20), or several pain measures.
Results for restrictive versus routine mediolateral and midline episiotomies were similar to the overall comparison.
Reviewers concluded that a policy of restrictive episiotomy appears to have several benefits over routine episiotomy: less posterior perineal trauma, less suturing, fewer complications, and no difference for most pain measures and severe vaginal or perineal trauma.
Risk of anterior perineal trauma with restrictive episiotomy was increased, however. Restrictive-use protocols, likely to be institution-specific, essentially curb episiotomy use by stating that the procedure should not be “routinely performed.” Instead, episiotomy is restricted to cases in which the clinician believes it is warranted. Examples of such situations include use of forceps, shoulder dystocia, and an estimated fetal weight above 4,000 g. As discussed, the data cannot support the value of episiotomy use even in these circumstances; however, simply discouraging routine episiotomy would effectively lower the rate to the desired 30% range.
Midline versus mediolateral incision. The most vocal debates focus on which type of episiotomy to perform and whether it should be performed earlier or later in the second stage of labor.
It has been proposed that by abandoning midline episiotomies in favor of the mediolateral technique, physicians can avoid injury to the sphincter and improve immediate birth outcome without compromising long-term function—though pros and cons of this approach are a subject of debate (see “Comparison of mid-line versus mediolateral episiotomy”).
Still, the data suggest that, when properly performed, median and mediolateral episiotomy have equivalent rates of satisfactory recovery,13 though the latter technique may require more technical skill for both its performance and repair.
Early versus late incision. Proponents argue that an episiotomy at the time the presenting part is crowning is “too little, too late.” They maintain that for the procedure to be truly protective, it should be utilized earlier in the second stage of labor.
Data are insufficient to confirm or refute the efficacy of early episiotomy. One would do well to remember, however, that early episiotomy was endorsed as a method to help shorten the second stage of labor when used in conjunction with prophylactic forceps delivery—a method that is now less prevalent in obstetric practice.
Strongest predictor of episiotomy: Private practice provider?
The category of obstetric provider—midwife, faculty, or private provider—may be the most reliable predictor of episiotomy. Interestingly, use of episiotomy increased in the 1920s as delivery moved from home to hospital and birth attendants shifted from midwives to physicians.
In a study of demographic variables and obstetric factors associated with episiotomy in spontaneous vaginal delivery, researchers examined 1,576 term, singleton, spontaneous vaginal deliveries in nulliparas. They found that midwives had the lowest episiotomy rate (21.4%), compared with residents and full-time faculty (33.3%) and private physicians (55.6%).15
After controlling for confounding factors with logistic regression, the authors determined that private practice provider was the strongest predictor of episiotomy, followed by faculty provider, prolonged second stage of labor, fetal macrosomia, and epidural analgesia.
The study concluded that the obstetric and demographic factors evaluated did not readily explain the link between type of provider and episiotomy rate. Numerous theories have been proposed, but factors that would clearly explain the differences have yet to be identified.