Episiotomy is the term for a surgical incision of the perineum made to increase the diameter of the vulval outlet during childbirth. Although episiotomy has become one of the most commonly performed surgical procedures in the world, it was introduced without strong scientific evidence of its effectiveness.


Since the 1970s, its routine use in the UK has been challenged. Episiotomy was submitted to randomized clinical trials, and reviews of these trials by Caroli and Belizan, 2004, concluded that there is only evidence to support the selective, and not routine use of episiotomy. Adverse effects of routine episiotomies;


  • An increase in the overall rate of posterior perinieal trauma
  • Increased risk of anal spincter damage
  • Weakened pelvic floor muscles, decreasing sexual function postpartum
  • Increased pain and pernial infection postpartum
  • Increased intrapartum maternal blood loss


Episiotomy rates in the UK in 2006-2007 were reduced to 13% of women, NHS Choices website.

Selective use of Episiotomy


Benefits found by Caroli and Belizan:


  • Reduction in the incidence of severe perineal tears, and thus preservation of pelvic floor. Postpartum sexual dysfunction, urinary/faecal incontinence and uterine prolapse are all subsequently reduced.
  • Easier repair and better healing of a straight, clean incision.
  • Reduced cranial trauma of newborn.



    Adverse Effects found by Caroli and Belizan:


    • Increased risk of anterior perineal trauma.
    • Increased  risk of vertical transmission of HIV


    Indications for Episiotomy


      • To accelerate delivery in cases of foetal distress, i.e. prolonged late decelerations or foetal bradycardia during active pushing
      • When the baby's shoulders are stuck (shoulder dystocia).
      • During instrumental delivery which can cause significant damage to the perineum i.e. a breech delivery with forceps.
      • To expidite delivery when birth is delayed by an unyielding perineum.
      • To reduce prolonged maternal pushing efforts in cases of severe hypertensive or cardiac disease.
      • As prophylaxis against soft-tissue-trauma, for example vaginal tears which are predicted to extend to the muscles, anal sphincter and anus. Imminent tears are indicated by a show of fresh blood when the presenting part of the foetus distends the perineum as the mother pushes.


        Types of Incision

        There are 2 main types of incision (see Figure 1 opposite). 


        1) Mediolateral/Posterolateral

        The incision starts midline at the frenulum of the labia minora, avoiding damage to the Bartholin’s gland. It is then directed diagonally to the left over the right side of the posterior perineum to a point midway between the anus and ischial tuberosity, avoiding the anal sphincter. 


        2) Midline

        The incision starts in the midline position and is made vertically towards the anus.


        Mediolateral vs. Medline

         Midline incisions bleed less and are easier to repair. However the incision carries a greater risk of extension into the rectum, hence it should only be used by the experienced. After reviewing clinical trials, Caroli and Belizan (2004) concluded that there was insufficient evidence to indicate which method was superior.      



        The decision to perform an episiotomy must be made on an individual basis and using clinical judgement, taking the woman’s wishes and obstetric history into consideration. The woman must be given information on episiotomy and consent obtained prior to labour, because it is difficult to obtain true informed consent during labour.



        Points to avoid in the Procedure


        Don't perform episiotomy too early because vaginal delivery may not be possible, and blood loss and discomfort are increased when mothers receive both a perineal and abdominal incision. Don't incise beyond the bony ischial tuberosities. Outlet obstruction due to bony structures is not relived by an episiotomy.


        Prevention of Episiotomy


        Controlled delivery of the head that allows gradual stretching of the perineal tissue can help in minimizing damage to the perineum. Perineal masage begining around the 34th week has been shown to reduce perineal damage by 6%, Shipman 1997.



        1.) NHS Choices Website


        2.) Carroli G, Belizan J (2004) Episiotomy for vaginal birth (Cochrane Review): In: The Cochrane Library, Issue 1 Chichester, UK: John Wiley and Sons, Ltd.


        3.) Shipman M, Boniface D, Tefft M, Mcloghry F (1997) Antenatal perineal massage and subsequent perineal outcomes: a randomised controlled trial.  British Journal of Obstetrics and Gynaecology 104: 787-791.


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