Routine episiotomy has been shown to cause more harm than good. Studies demonstrate that restrictive episiotomy policies are associated with less posterior perineal trauma, less suturing, and fewer complications, with no difference for most pain measures or severe vaginal and/or perineal trauma. When the perineum is preventing delivery, particularly if the fetal heart rate is abnormal, an episiotomy may expedite a vaginal birth.
Sources:
Carroli G, et al. Episiotomy for vaginal birth. Cochrane Database Syst Rev. 2000;(2):CD000081. PMID: 10796120.
Lee L, et al. Management of Spontaneous Labour at Term in Healthy Women. J Obstet Gynaecol Can. 2016 Sep;38(9):843-865. PMID: 27670710.