Perineal trauma: A women's health and wellbeing issue

Female genital mutilation

It is vitally important to discuss the options women who have had female genital mutilation/cutting (FGM/C) performed as they are at an increased risk of third- and fourth-degree tears (Gayle, 2016). To reduce the risk of severe perineal trauma in women with FGM, women need to be identified early in the antenatal period (Gayle, 2016). Early recognition of women with FGM during pregnancy allows time to explore the concerns and discuss options for birth and follow-up care.

Hands-on or hands-poised?

There is an ongoing debate as to whether hands-on or hands-poised is beneficial or not. The hands-on technique aims to reduce perineal trauma by slowing down the birth of the baby's head and decreasing the presenting diameter of the fetal head through the maintenance of flexion and with manual perineal protection. The hands-poised technique involves being ready to apply light pressure on the baby's head to avoid rapid expulsion.

The hands-on or hands poised (HOOP) study (McCandlish et al, 1998) was the first randomised controlled trial that compared different techniques of perineal protection during the second stage. This trial examined a sample of 5471 women and reported that the hands-on group were less likely to report mild pain in the previous 24 hours at 10 days after giving birth when compared to women in the hands-poised group (31.1% v 34.1%; relative risk 1.10; 95% CI 1.01–1.18); but had increased episiotomy rates (12.9% v 10.2%; relative risk 0.79; 95% CI 0.65 to 0.96). No statistical differences were reported for third- or fourth-degree tears.

A Cochrane review (Aasheim et al, 2017) found that a hands-poised technique reduced the rate of episiotomy but no differences on the rates of intact perineum, perineal trauma requiring suturing or any severity of perineal trauma were found. However, findings were based on moderate-to-low quality evidence and should be considered with caution. A modified systematic literature review undertaken by Petrocnik and Marshall (2015) highlighted that when a hands-poised technique was used, reduced rates of episiotomy and perineal trauma were found. Use of the hands-on technique resulted in increased perineal pain after birth.

However, a cohort study undertaken in Norway (Laine et al, 2012) and a population-based study in the UK (Naidu et al, 2017) have reported that a hands-on technique reduced the rates of severe perineal trauma. A systematic review of findings from observational studies also supports this claim (Bulchandani et al, 2015).

A UK interventional study that introduced clinical education with specific training on the hands-on technique reported that it could reduce the risk of major obstetric and anal sphincter injuries (Naidu, 2017). The sample included 11 135 women who had a vaginal birth, and midwives and doctors were instructed to support the perineum. The SPT rate decreased from 4.7% to 4.1%, which was not statistically significant (P=0.11), but multivariate analysis found a significant decrease in SPT associated with perineal support (23%; odds ratio (OR) 0.77, 95% CI 0.63–0.95; P=0.01). An earlier Norwegian study (Hals et al, 2016) that introduced an interventional programme to reduce the incidence of anal sphincter tears reported similar findings.

In contrast, Lee et al (2018) recommended that a hands-poised, undirected approach could be used to prevent moderate and severe perineal injury. The researchers carried out a retrospective cross-sectional study, reviewing data from a metropolitan maternity hospital and a private maternity hospital in Brisbane, Australia. Data were collected on clinicians' instructions to women during the second stage of labour and hand position at birth. A sample of 23 393 term women who gave birth vaginally without the intervention of forceps or ventouse to a singleton infant between January 2011 to December 2016 was included in the analysis. These findings demonstrated that there was no difference in the risk of moderate or severe perineal injury when reviewing the data on different techniques for nulliparous women, but there was a significant difference for multiparous women: the hands-on/directed approach was associated with an increase risk of sustaining moderate perineal injury (adjusted odds ratio (AOR) 1.18; 95% CI 1.10–1.27; P<0.001) and severe perineal injury (AOR 1.50; 95% CI 1.20–1.88; P<0.001).

A prospective observational study of 3902 women undergoing vaginal birth in the UK involving the implementation of the Stop Traumatic OASI Morbidity Project (STOMP), a quality improvement bundle led to a reduction in SPT rate from 4.7% to 2.2% at 1 year after implementation (Basu et al, 2016). The STOMP bundle is based on three key clinical practice components: ‘position’, ‘coach’, and ‘speed’. ‘Birth position’ included avoiding semi-recumbent and lithotomy positions and supporting women to adopt an upright position. ‘Coaching’ involved effectively communicating with women during the second stage to support them to have a more controlled and slow birth, avoiding directed pushing and encouraging pushing when they feel the urge to do so. ‘Speed’ involved using simple, tactile (flat hand) support on the baby's head and no manual perineal protection. Reports of long-term outcomes of 8782 vaginal births confirmed that STOMP could lead to a significant decrease in SPT (Basu and Smith, 2018). There was also a significant decrease in the mean incidence of SPT relative to the 9 months before implementation of STOMP (P<0.001). Further implementation of STOMP and a follow-up audit of change in clinical practice in other maternity settings may confirm these findings.

The OASI Care Bundle Project, a collaboration between RCOG and the Royal College of Midwives (RCM) funded by The Health Foundation is ongoing and includes a hands-on technique for all spontaneous births and all assisted instrumental deliveries as one of the evidence-based interventions (RCOG, 2018).

However, there is conflicting and inconclusive evidence to support either a hands-on or hands-poised technique. There is evidence that demonstrates that a hands-poised approach is associated with a decreased risk of an episiotomy being performed and less perineal pain, and it is unclear if a hands-on technique contributes to a reduction in the risk of severe perineal trauma. The choice of whether to use a hands-on or hands-poised technique should be determined by the clinical judgment of a midwife at the time of birth with the woman's informed consent.

Alternatively, it appears that warm compresses applied to the perineum during second stage of labour can reduce the rates of severe perineal trauma, yet this is not included as one of the evidence-based interventions in the OASI UK care bundle. A Cochrane review has reported a significant reduction in the incidence of third- and fourth-degree tears when warm compresses were applied to the perineum (risk ratio 0.48; 95% CI 0.28–0.84) (Aasheim et al, 2017). This good evidence supports the recommendation that warm compresses should be offered to women and applied to the perineum during the second stage of labour as a preventative measure to reduce the risk of severe perineal trauma.

Episiotomy

The literature highlights that even though episiotomy rates have decreased considerably during the past few decades, there is still wide variation in rates globally and a right medio-lateral and midline incision are the two common types performed (Euro-Peristat et al, 2013; Steen and Cummins, 2016b). This indicates that evidence is often not being put into clinical practice and that non-evidence-based clinical procedures prevail (Diorgu et al 2016a; 2016b). A Cochrane systematic review confirmed earlier findings that selective use of episiotomy in women (in a normal birth without the need for forceps) meant that fewer women has severe perineal trauma, and that there were no benefits of routine episiotomy for the baby or the mother (Jiang et al, 2017). In addition, it has been reported that episiotomy does not protect a preterm head from intracranial haemorrhage and that it should not be performed for this reason (Adams, 2013). However, restricted use of episiotomy is now recommended for breech birth (RCOG, 2006). Sartore et al (2004) has reported that a right medio-lateral incision can damage the levator ani muscles and is associated with a substantial decline in pelvic floor strength and dyspareunia. NICE (2017) recommends that an episiotomy should not be performed to avoid a third- or fourth-degree tear, as there is insufficient evidence to justify this claim, but research demonstrates that this misapprehension is still believed by some midwives and obstetricians (Diorgu et al, 2016a; 2016b).

Justifications for episiotomy

For a woman with FGM classified by the World Health Organization (WHO) (2018) as Type II or Type III (Figure 1), an episiotomy may be advocated (Hakim, 2001) and may be necessary to facilitate an instrumental birth (Berggren, 2013). Episiotomy may be considered when shoulder dystocia occurs to improve access and enable a midwife or obstetrician to undertake manoeuvres to assist with the birth of a baby (American Academy of Family Physicians, 2012). Therefore, it appears there is some clinical justifications to perform an episiotomy when there is an indication to intervene.

More recently, it has been recommended that when an episiotomy is clinically deemed necessary, a right mediolateral episiotomy incision should be performed between 45–60° angle from the fourchette with a single cut, approximately 4–5 cm in length (NICE, 2017). Kalis et al (2008) found that the angle of incision is significantly different to the angle that the sutured incision rests post-birth. A randomised controlled trial undertaken in Egypt compared a 60° v 40° incision when performing mediolateral episiotomy in primiparous women and reported no significant differences in the rates of third- or fourth-degree tears, but found increased short-term pain with a 60° incision (El-Din et al, 2014). The skills of the midwife or obstetrician also play a significant role in the outcomes of the episiotomy. This has led to the development of specifically designed scissors (Episcissors60) in the UK (NICE, 2015b). These scissors have been designed to aid a midwife or obstetrician to perform a medio-lateral episiotomy and attain a post-suturing angle of 40-60°, reducing errors in estimating the angle for the incision (van Roon et al, 2015). However, there is presently limited evidence of the benefit of using these scissors and further research is required to justify the use and cost.

Perineal body length is measured from the fourchette to the midpoint of the anal canal and has recently been identified as a risk factor for SPT by Geller et al (2014). The average perineal body length in women is 37–38 mm (van Roon et al, 2015) and research has shown that women with a perineal body length less than 25 mm have a significantly increased risk of sustaining SPT (40% v 5.6% P=0.004) (Deering et al, 2004). Kapoor et al (2015) reported that there was evidence to suggest that the perineal distention during crowning increases the perineal body length by 50% vertically, 170% horizontally and between 50-10% angularly. Further research is therefore needed to evaluate if a perineal body length less than 25 mm increases a woman's risk of severe perineal trauma and is a justification for an episiotomy.

Skills to repair perineal trauma

Several studies have demonstrated that the success of a perineal repair and morbidity outcomes for women is directly linked to the skills and knowledge of the health professional performing the repair (Selo-Ojeme et al, 2009; Cioffi et al, 2010; Bick et al, 2012a; Wilson, 2012; Dudley et al, 2013; Zimmo et al, 2017). The outcomes of perineal repair have been directly linked to three key factors: the type of suture material used in the repair (Kettle et al, 2010); the suturing technique used (Kettle et al, 2012; Selo-Ojeme et al, 2015) and the knowledge and skills of the operator (Dahlen and Homer, 2008; Bick et al, 2012b; East et al, 2015; Selo-Ojeme et al, 2015; Frost et al, 2016).

A systematic review by Smith et al (2013) found a significant lack of knowledge regarding perineal wound assessment and classification among midwives and obstetricians. This has considerable implications in practice, as a poor understanding of perineal anatomy, assessment and repair can lead to the misclassification and an inadequate repair of perineal trauma. Midwives and obstetricians attributed this deficit of knowledge to a lack of structured educational training in undergraduate programmes and in clinical practice. Other studies support these findings (East et al, 2015; Selo-Ojeme et al, 2015; Zimmo et al, 2017). This evidence suggests that there is an urgent need to provide perineal wound care educational training, firstly in undergraduate programmes and for this to be continued in clinical practice upon qualifying as a component of continual professional practice development.

Postnatal perineal trauma care

NICE (2017) has recommended that women should be asked at each postnatal contact whether they have any concerns about the healing of a perineal injury.

Regular observation is used to evaluate perineal trauma and healing after birth. Standardised scales to assess the consequences of perineal injury are not readily available for midwives to use in clinical practice, even though several scales have been developed and used in research studies (Steen, 2010). Formal clinical evaluation still appears to be a neglected area of women's healthcare and an identified area for further research.

It is recommended that women continue to practise pelvic floor exercises (both fast- and slow-twitch muscle exercises) postnatally as a preventative measure for urinary incontinence (Boyle et al, 2012; Clarkson et al, 2014). Evidence is limited to support this recommendation, but systematic reviews have found some benefits to routinely practising pelvic floor exercise, such as a reduction in urinary continence problems (Mørkved, 2013; Boyle et al, 2012).