In nulliparous women, selective midline episiotomy may help reduce the risk of third-degree perineal lacerations, when compared to routine episiotomy, according to the results of a study published in the March issue of the American Journal of Obstetrics and Gynecology.
Alexander Rodriguez, MD, of the Antioquia University Medical School in Medellin, Colombia, and colleagues randomly assigned 446 nulliparous women with deliveries after at least 28 weeks' gestation to undergo either routine episiotomy or selective episiotomy, which was performed only in cases of forceps delivery, fetal distress, shoulder dystocia, or when the attending physician anticipated a severe laceration.
The researchers found that the rate of third- or fourth-degree perineal lacerations was significantly higher in patients who underwent routine episiotomy compared to those who underwent selective episiotomy (14.3 % vs. 6.8%). Further analysis showed that only the reduction in third-degree lacerations was significant. But they also found that periurethral, labia minora, and superficial vaginal lacerations were significantly more common in the selective episiotomy group.
"Our study is the first randomized clinical trial in the world comparing the routine use of midline episiotomy versus the use of selective midline episiotomy in nulliparous patients in the prevention of third- and fourth-degree lacerations," the authors conclude. "We recommend performing selective episiotomy in all birth centers when caring for nulliparous women."
Rodriguez A, Arenas EA, Osorio AL, et al. Selective vs routine midline episiotomy for the prevention of third- or fourth-degree lacerations in nulliparous women. Am J Obstet Gynecol. 2008;198:285.e1-.e4. doi:10.1016/j.ajog.2007.11.007.