Updated: September 2019
Most women will sustain some damage to their perineum during birth (AIHW 2018). Around 50% will have a tear or graze in the skin and/or vaginal wall (1st / 2nd degree). Occasionally (1% of non-instrumental vaginal births) significant tearing occurs that extends into the anal sphincter (3rd / 4th degree). You can find out more about types/grading of perineal trauma here. This post will discuss ‘protecting the perineum’ and was initially based on a literature review. You can find the full literature review and reference list in my thesis. I have updated the post regularly since then and have added new references in the text.
Care providers often consider themselves to be ‘perineal protectors’ tasked with preventing women from tearing. There is currently a lot of effort and money being put into trying to reduce significant tearing (see this post). And of course the approach taken to ‘protect the perineum’ reflects the birth culture in general ie. that women’s bodies are dangerous, and risk management involves carrying out interventions to minimise that risk. I think the truth is the other way around. What we do is usually the risk, and risk management should be about supporting physiology and instinct. Only intervening when there is a deviation from physiology.
Before I get off my soapbox and share the research evidence…
Bear in mind – research about birth outcomes is carried out on general populations i.e primarily on women having medically managed births. These types of births often involve interventions that increase tearing eg. syntocinon, directed pushing, etc. We really don’t have any good research on what protects the perineum during an uninterrupted, physiological birth where tearing rates are much lower.
Some factors that increase the chance of tearing are impossible or very difficult to control (Dahlen et al. 2015):
- a big baby
- first vaginal birth
- high weight gain in pregnancy
- higher socioeconomic circumstances
- older and younger maternal age
- ethnicity (Caucasian and Asian)
- short perineal body
- nutritional status
- abnormal collegan synthesis
Preparing the perineum for birth
Suggesting there is a need to ‘prepare’ for birth contradicts the fact that women’s bodies are perfectly capable of preparing for birth without intervention. However, perineal stretching massage can increase some women’s confidence in their body’s ability to stretch and open for their baby. On the other hand, plenty of women don’t prepare in this way, and whether you have confidence in your body or not, your perineum will stretch.
A number of guidelines recommend that women should be encouraged to massage their perineums during pregnancy to reduce the chance of tearing. The reference cited to support this recommendation is a Cochrane Review. However, the review did not conclude that massage reduced the chance of tearing. It found that women having their first baby who did perineal massage were less likely to have an episiotomy – not a tear. This suggests that care providers act differently in these cases – and needs further investigation. Perhaps perineal massage helps women to fit unnecessary birthing timeframes prescribed by hospitals, therefore avoid being cut?
There is a rather scary device called an Epi-No designed to use during pregnancy to stretch the perineum. A large RCT found that “antenatal use of the Epi-No device is unlikely to be clinically beneficial in the prevention of intrapartum levator ani damage, or anal sphincter and perineal trauma.” Personally I worry about potential long term effects of repeatedly stretching the perineum to the size of a babies head. Although a woman may give birth a number of times during her life, she will usually have more than a day between each baby’s head stretching her vagina. It is also a reflection of our technocratic culture that a ‘device’ is considered to be necessary in order to prepare for childbirth.
Birth is where all of the care provider activity focuses. It was seeing all of the fussing and fiddling carried out as babies were born that sent me in the direction of a PhD. I could not understand why such a physiological and instinctive bodily process required so much directing and doing. I still don’t. I suggest that before (or after) you read this post, you read supporting women’s instinctive pushing behaviour during birth. Of course, most women do not have an undisturbed birth – therefore are not necessarily connected in with what is going on in their body. In these cases it may be appropriate to intervene (with consent).
General factors known to increase the chance of tearing during birth are (Dahlen et al. 2015):
- position of baby – larger diameter of head presenting
- midline episiotomy (see below)
- instrumental birth – particularly forceps
- ‘prolonged second stage’ – likely because this results in an instrumental birth
- syntocinon (pitocin) use in women having their second or more vaginal birth
- shoulder dystocia
There are two main principles involved in reducing the chance of tearing:
- A slow birth of the baby through the vagina – allowing time for the tissues to respond and stretch
- Capacity for stretch and ‘give’ in the tissues
Some birth positions assist with the principles above. The two positions that involve the least chance of tearing (side lying and hands/knees) do not involve stretched wide legs and therefore perineums. In addition the pressure of the baby’s head is towards the front of the mother rather than directly onto the perineum. In contrast, positions that make the perineum tight and stretched, and place all of the pressure of the baby’s head directly onto the perineum increase the chance of tearing: semi-supine (sitting upright and reclined – the TV/film birth position); squatting; and lithotomy.
Some women will close their legs during crowing. I have seen midwives push women’s legs back open or say ‘keep your legs open’. Closing the legs, or bringing them in from a wide-open position protects the perineum. Try it yourself… open your legs wide and bring them up towards your chest – stranded beetle position – and feel what happens to your perineum. Now close your legs a little and bring them down away from your chest – feel how much more ‘give’ there is in your perineum when it is not stretched out. It can now respond to the stretch required by the baby’s head without also being stretched out sideways. As for whether closing your legs will stop a baby from coming out… it may slow it down, but that baby is coming out. I have seen a woman birth on her side with her legs crossed – her baby came out from behind.
Standing up-right can result in a quick birth – particularly for women who have previously given birth – increasing the chance of tearing. It is not a position many women stay in to birth unless they have been directed to get into it.
Guidelines and training are reinforcing the need for the care providers to ‘visualise the perineum’ during birth. I’m not sure how that is supposed to prevent tearing. However, it does increase the chance the care provider will intervene. This approach is leading to more women being directed into positions to facilitate this – unfortunately positions that increase the chance of tearing.
Guidelines recommend that ‘good communication’ is required between the care provider and woman to ensure a slow birth and minimise tearing. However, this is unnecessary if the woman is birthing instinctively. The intense sensations experienced during crowning usually result in the woman ‘holding back’ while the uterus continues to push the baby out slowly and gently. Often women will hold their baby’s head and/or their vulva. I have witnessed one mother attempt to push her baby back in (you know who you are) – it was unsuccessful but gave us a giggle afterwards. Telling a woman to stop pushing, pant or ‘give little pushes’ distracts her at a crucial moment, and suggests that you are the expert in her birth, which you are not. She is the one with a baby’s head in her vagina – leave it to her. Of course, if you have been shouting at her to ‘Puuuush’ with every contraction before crowning – she will be listening to you, not her body…
Some women find having a warm compress held against their perineum as the baby crowns helps to ease the sensations of stretching. Others, hate it and find it intrusive. A Cochrane review found that warm compresses did not increase the chance of having an intact perineum or decrease the chance for suturing. However, it did reduce the chance of a very severe tear (3rd or 4th degree).
Waterbirth is another way of bathing the perineal tissue in warm water – and unlike warm compresses, makes it difficult for anyone apart from the birthing woman to touch her perineum or baby during birth.
‘Hands on’ techniques
Hands on techniques aimed at slowing the birth of the baby and supporting the perineal tissues are routinely used by many care providers. However, a systematic literature review concluded that: “The hands-poised [off] technique appeared to cause less perineal trauma and reduced rates of episiotomy. The hands-on technique resulted in increased perineal pain after birth and higher rates of postpartum haemorrhage.” A Cochrane Review found that ‘hands on’ techniques did not reduce the chance of tearing and increased the chance of having an episiotomy. And a recent Australian study found that ‘hands on’ increased the chance of tearing for women having their second or more vaginal birth.
No research has explored women’s experiences of a ‘hands on’ approach. And, I am yet to hear a midwife or obstetrician ask for permission before placing their hands on the woman and baby.
Massaging the perineum as the baby is trying to be born concerns me for a number of reasons. It makes me really uncomfortable to watch lots of ‘activity’ being done to a woman’s body while she is trying to birth. I have seen some very brutal versions of ‘perineal massage’ done to women; and I am guessing/hoping that most of the women in these studies had epidurals. However, the Cochrane Review above suggests that this type of massaging can reduce the chance of significant tears (3rd and 4th degree) not the usual (1st and 2nd degree). Significant tearing is rare (around 3%) – so the intervention needs to be weighed up with the risks of additional pain and disturbance to physiology. Also, in order to perform this intervention effectively the woman needs to be in a position that increases her chance of tearing ie. on her back / semi-reclined.
An episiotomy involves a deep cut into the perineal muscles and skin ie. creating perineal trauma. Episiotomies used to be rare in midwifery practice. I have carried out three in my career, and with hindsight I think two were unnecessary. However, there is a resurgence thanks to a new wave of perineal focused intervention packages, and confusing research summaries and clinical guidelines.
For example, a Cochrane Review examining ‘selective’ vs ‘routine’ episiotomy concluded that: “In women where no instrumental delivery is intended, selective episiotomy policies result in fewer women with severe perineal/vaginal trauma.” This seems to have been interpreted as ‘selective episiotomy reduces severe tearing’ rather than ‘in comparison to routine episiotomy’. Interestingly, the review does not include information about what indications are included in a ‘selective’ approach, or the evidence supporting those indications.
Clinical guidelines include indications for episiotomy without citing research to support those statements. For example, NICE guidelines state that an episiotomy should only be carried out if needed for an instrumental birth, or severe fetal distress. This was the standard when I trained and resulted in very few episiotomies. However, QH guidelines have recently added in additional indicators including ‘soft tissue dystocia’. The citation for this statement is another guideline (RANZOG) – and that guidelines includes no supporting evidence for the statement. ‘Soft tissues dystocia’ refers to a perineum not stretching ‘quick’ enough ie. lack of patience. In practice, care providers are cutting women if they think they may tear or if the birth is not quick enough – believing these are appropriate indications.
There is some evidence about outcomes relating to the types of episiotomies used – mid-line (down toward the anus) vs medio-lateral (60 degree angle). A mid-line episiotomy contributes to the risk of severe perineal trauma by increasing the chance the cut will extend (Lappen & Gossett 2014). However, a medio-lateral episiotomy cuts through more nerves and perineal structures (Patel et al. 2018). We are only just beginning to understand the complex anatomy of the clitoris – a structure that is cut during a medio-lateral episiotomy. This type of episiotomy is associated “with a decreased sexual functioning as well as sexual desire, arousal and orgasm within postpartum five years” (Dogan et al. 2017).
Even if episiotomy does reduces the chance of severe tearing (which we don’t have the evidence for) – having an episiotomy during a non-instrumental vaginal birth would be trading a 1% chance of significant tearing with 100% chance of perineal damage via a cut.
Tearing is a normal part of the birth process, and the body usually heals well. The vaginal wall is a mucous membrane and heals very fast (like the mouth). Suturing is the most common method of perineal repair. Whether to suture or not should be the woman’s decision. In relation to 2nd degree tears (the most common) the need to suture is debatable if the tear aligns well and is not bleeding. A Cochrane Review concluded:
“…at present there is insufficient evidence to suggest that one method is superior to the other with regard to healing and recovery in the early or late postnatal periods. Until further evidence becomes available, clinicians’ decisions whether to suture or not can be based on their clinical judgement and the woman’s preference after informing them about the lack of long-term outcomes and possible chance of slower wound healing process, but possible better overall feeling of well being if left un-sutured.”
In my own experience as a midwife I have found that un-sutured perineums heal very quickly and with far less pain than sutured perineums. Now-a-days my suturing skills are mostly utilised in teaching suturing.
There is very little care providers can do to protect women’s perineums using interventions. Instead, we need to encourage women to trust that their body has an innate ability to birth their baby; that perineal tearing is a normal part of birth; and that the body will heal itself.