III Methodology
Basic principles
The method used to prepare this guideline was determined by the class to which this guideline was assigned. The AWMF Guidance Manual (Version 1.0) has set out the respective rules and
requirements for different classes of guidelines. Guidelines are differentiated into lowest (S1), intermediate (S2), and highest (S3) class. The lowest class is defined as consisting of a
set of recommendations for action compiled by a non-representative group of experts. In 2004, the S2 class was divided into two subclasses: a systematic evidence-based subclass (S2e) and a
structural consensus-based subclass (S2k). The highest S3 class combines both approaches.
This guideline was classified as: S2k
Grading of recommendations
The grading of evidence based on the systematic search, selection, evaluation and synthesis of an evidence base which is then used to grade the recommendations is not envisaged for S2k
guidelines. The different individual statements and recommendations are only differentiated by syntax, not by symbols ([Table 3 ]):
Table 3 Grading of recommendations (based on Lomotan et al., Qual Saf Health Care 2010).
Description of binding character
Expression
Strong recommendation with highly binding character
must/must not
Regular recommendation with moderately binding character
should/should not
Open recommendation with limited binding character
may/may not
Statements
Expositions or explanations of specific facts, circumstances or problems without any direct recommendations for action included in this guideline are referred to as “statements”. It is
not possible to provide any information about the level of evidence for these statements.
Achieving consensus and level of consensus
At structured NIH-type consensus-based conferences (S2k/S3 level), authorized participants attending the session vote on draft statements and recommendations. The process is as follows. A
recommendation is presented, its contents are discussed, proposed changes are put forward, and all proposed changes are voted on. If a consensus (> 75% of votes) is not achieved, there is
another round of discussions, followed by a repeat vote. Finally, the extent of consensus is determined, based on the number of participants ([Table 4 ]).
Table 4 Level of consensus based on extent of agreement.
Symbol
Level of consensus
Extent of agreement
+++
Strong consensus
> 95% of participants agree
++
Consensus
> 75 – 95% of participants agree
+
Majority agreement
> 50 – 75% of participants agree
–
No consensus
< 51% of participants agree
Expert consensus
As the term already indicates, this refers to consensus decisions taken specifically with regard to recommendations/statements issued without a prior systematic search of the literature
(S2k) or where evidence is lacking (S2e/S3). The term “expert consensus” (EC) used here is synonymous with terms used in other guidelines such as “good clinical practice” (GCP) or “clinical
consensus point” (CCP). The strength of the recommendation is graded as previously described in the chapter Grading of recommendations but without the use of symbols; it is only
expressed semantically (“must”/“must not” or “should”/“should not” or “may”/“may not”).
IV Guideline
1 Epidemiology
Consensus-based recommendation 1.E1
Expert consensus
Level of consensus +++
If an episiotomy is indicated, the incision should be made in a mediolateral direction to prevent the incision from injuring the anal sphincter.
According to the Austrian Registry of Births, in 2017 a 3rd degree perineal tear during vaginal birth occurred in 1.9% of cases and a 4th degree perineal tear in 0.1%. 3.1% of primiparous
women suffered a 3rd degree perineal tear and 0.2% had a 4th degree perineal tear. The respective figures for multiparous woman were 0.9% (grade 3 PT) and 0.1% (grade 4 PT) [1 ].
In Germany, the respective incidences for the year 2017 were 1.74% (grade 3 PT) and 0.12% (grade 4 PT). There were no data on the respective incidence in primiparous and multiparous women
[2 ].
In contrast to these figures, a systematic review reported an incidence of 11% for tears of the external or internal anal sphincter [3 ].
In recent years, the reported incidence of high-grade perineal tears has increased. This increase has primarily been attributed to improvements in the detection rate [4 ], [5 ], [6 ].
Symptoms subsequent to perineal tears include flatulence incontinence, pathological urge to defecate and, more rarely, fecal incontinence with the consistency ranging from watery to firm
stools. The frequency of these symptoms tends to increase over the years following the birth [7 ], [8 ], [9 ].
According to the literature [5 ], [10 ], [11 ], [12 ], [13 ], [14 ], [15 ], [16 ], [17 ], [18 ], [19 ], [20 ], [21 ], [22 ], [23 ], [24 ], [25 ], [26 ], [27 ], [28 ], [29 ], [30 ], [31 ], [32 ], [33 ], [34 ], the list of risk factors in descending order of importance (the respective odds ratios (OR) are given in brackets)
are:
use of forceps during the birth (OR 2.9 – 4.9)
a birth weight of > 4 kg or an occipital frontal circumference of > 35 cm (OR 1.4 – 5.2; it increases with the birth weight of the infant)
a median episiotomy (OR 2.4 – 2.9)
nulliparity (OR 2.4)
vacuum extraction delivery (OR 1.7 – 2.9)
status post female genital mutilation (OR 1.6 – 2.7)
occiput posterior position of the fetus (OR 1.7 – 3.4)
shoulder dystocia (OR 2)
prolonged second stage of labor (OR 1.2 – 3.9)
Kristeller maneuver/fundal pressure (OR 1.8)
delivery in the lithotomy position or squatting position (OR 1.2 – 2.2)
Risk-reducing factors are [5 ], [10 ], [11 ], [12 ], [13 ], [14 ], [15 ], [16 ], [17 ], [18 ], [19 ], [20 ], [21 ], [22 ], [23 ], [24 ], [25 ], [26 ], [27 ], [28 ], [29 ], [30 ], [31 ], [32 ], [33 ], [34 ]:
selective episiotomy (OR 0,7)
mediolateral episiotomy during operative vaginal birth (OR 0,2 – 0.5)
damp perineal compresses (OR 0.5)
perineal massage performed antenatally or during the birth (OR 0.5)
The following obstetric measures are not prophylactic, but they also do not increase the risk of high-grade perineal lacerations [5 ], [10 ], [11 ], [12 ], [13 ], [14 ], [15 ], [16 ], [17 ], [18 ], [19 ], [20 ], [21 ], [22 ], [23 ], [24 ], [25 ], [26 ], [27 ], [28 ], [29 ], [30 ], [31 ], [32 ], [33 ], [34 ]:
timing and type of pushing
water birth
Ritgenʼs maneuver
vaginal balloon dilatation during pregnancy
“hands-on” vs. “hands-off” approach: “hands-off” means that no episiotomy will be carried out but this has no effect on perineal tears.
The following obstetric measures could not yet be definitively assessed:
Induction of labor with initiation of uterine contractions
Maternal obesity
Epidural anesthesia
The role of episiotomy with regard to parity and the angle of incision also requires further investigation.
2 Classification
Perineal lacerations are classified as higher grade when the trauma includes injury to the external anal sphincter [35 ]:
Grade 3 perineal tear: injury to the anal sphincter complex, rectal wall is intact
Grade 4 perineal tear: injury to the anal sphincter complex, injury to the anorectal mucosa
The following subdivision of grade 3 perineal tears is useful [36 ]:
3a: less than 50% thickness of the external anal sphincter is torn
3b: more than 50% thickness of the external anal sphincter is torn
3c: external and internal anal sphincter are torn
As the internal anal sphincter plays an important role in maintaining the mechanism of continence, every attempt must be made to identify any trauma to the internal anal sphincter in cases
of extended perineal trauma [37 ], [38 ].
Tearing of the anal epithelium while the internal anal sphincter remains intact (buttonhole tear) is a special type of high-grade perineal laceration. It is rare but if it remains
untreated, there is a real risk of developing a rectovaginal fistula. It can be diagnosed postpartum using anal palpation [39 ], [40 ], [41 ]. If the anorectal mucosa has torn while the external anal sphincter remains intact, there is a higher probability of injury to the internal
anal sphincter. The conclusive identification of this type of injury is only possible with surgery or using transanal endosonography [42 ], [43 ].
3 Diagnosis
Consensus-based recommendation 3.E2
Expert consensus
Level of consensus +++
In cases where the extent of injury is not clear, an experienced physician with specialist expertise (preferably a specialist for gynecology and obstetrics or a consultant with
coloproctological expertise) must be called in.
Consensus-based recommendation 3.E3
Expert consensus
Level of consensus +++
If there is any doubt, the diagnosis should be high-grade perineal tear.
After every vaginal birth, a 3rd and 4th degree perineal tear must be excluded by careful initial inspection and/or palpation by the obstetrician and/or the midwife. The use of vaginal and
anorectal palpation to assess birth trauma is extremely important. Both vaginal and rectal palpation are expressly recommended to assess the extent of injury for any perineal tear which is
grade 2 or above.
If it is not possible to exclude a grade 3 perineal tear, an experienced physician with specialist expertise (preferably a specialist for gynecology and obstetrics or a consultant with
coloproctological expertise) must be called in to confirm the suspected diagnosis, provide a general classification of the injury (grade 3 or grade 4 perineal tear) as guidance and initiate
further action.
4 Postpartum management
Consensus-based recommendation 4.E4
Expert consensus
Level of consensus +++
Treatment of a grade 3 or 4 perineal tear must be carried out under sufficient regional or general anesthesia to achieve maximum relaxation of the sphincter muscles while ensuring
ensure optimal visualization of the area requiring surgery.
Consensus-based recommendation 4.E5
Expert consensus
Level of consensus +++
Grade 3 and 4 perineal tears must be treated in a suitable operating room with sufficient lighting. Appropriate instruments with non-traumatic clamps must be available. The
operating surgeon must have an assistant.
Completely aseptic conditions may be beneficial in selected cases.
Consensus-based recommendation 4.E6
Expert consensus
Level of consensus +++
When treating a 3rd or 4th degree perineal tear, the surgical team must include a specialist with sufficient expertise (preferably a specialist for gynecology and obstetrics or a
consultant with coloproctological expertise). In exceptional cases, surgery may be delayed for up to 12 hours postpartum to ensure that treatment will be carried out by a
specialist.
Consensus-based recommendation 4.E7
Expert consensus
Level of consensus +++
When treating grade 3 or 4 perineal tears, patients should receive a single perioperative dose of an antibiotic.
Consensus-based recommendation 4.E8
Expert consensus
Level of consensus +++
Atraumatic, slowly absorbable sutures should be used to suture grade 3 or 4 perineal tears.
Consensus-based recommendation 4.E9
Expert consensus
Level of consensus +++
Placement of a bowel stoma must not be carried out during primary surgery of a high-grade perineal tear.
4.1 Preparation
Management of a 3rd or 4th degree perineal care requires general or regional anesthesia to achieve maximum sphincter relaxation and sufficient pain relief. The procedure is carried out
under aseptic conditions in an operating room or an equivalent facility with assistants, appropriate instruments and equipment. The patient is placed in the lithotomy position. The
surgical team must include a specialist with sufficient experience [44 ]. However, the number of previous operations does not appear to be relevant with
regard to avoiding anal incontinence [45 ].
In exceptional cases, surgery may be delayed for up to 12 hours postpartum [46 ]. Adequate documented preoperative informed consent is required unless it is
an emergency.
Patients should receive a single perioperative dose of an antibiotic [47 ].
4.2 Surgical strategy
Identification of additional birth trauma and precise classification of the perineal tear based on a speculum examination and a rectal examination ([Fig. 1 ]).
Fig. 1 Initial situation (with the kind permission of Dr. Eva Polsterer). [rerif]
If necessary, cervical and high vaginal tears must be treated first, working from the inside to the outside, before treating the perineal tear.
For 4th degree tears: repair the anorectal epithelium using atraumatic end-to-end 3-0 sutures [48 ], [49 ].
If the ends of the internal anal sphincter can be identified, the edges should be approximated using atraumatic interrupted mattress sutures, preferably 3-0 sutures [49 ], [50 ].
The ends of the external anal sphincter must be identified and gripped with Allis clamps.
The external anal sphincter must be sutured with atraumatic U-sutures, preferably 2-0 sutures. There is a choice between 2 methods for the repair: an overlapping technique and an
end-to-end technique ([Figs. 2 ] und [3 ]) [51 ], [52 ], [53 ]. The end-to-end technique should be used if the muscle has not torn completely [45 ], [54 ]. The overlapping technique reduces symptoms of fecal urgency and fecal incontinence after 1 year, but after 3 years no differences were found between the
two techniques [55 ]. There is some evidence that using the end-to-end technique reduces the flatulence rate [54 ]. It is
not possible to give a definitive recommendation about the best surgical method. The surgeon should use the method he/she is most familiar with.
Fig. 2 Overlapping technique (with the kind permission of Dr. Eva Polsterer). [rerif]
Fig. 3 End-to-end technique (with the kind permission of Dr. Eva Polsterer). [rerif]
The perineum must be repaired layer by layer.
Birth injuries must be recorded and an operative report must be written.
Atraumatic slowly absorbable sutures should be used for items 2 – 6. The choice between braided or monofilament sutures is up to the surgeonʼs individual preference [50 ], [51 ], [52 ], [53 ]. Placement of a bowel stoma is not
indicated [56 ], [57 ].
Consensus-based recommendation 4.E10
Expert consensus
Level of consensus +++
For 4th degree perineal tears, the anorectal epithelium should be repaired using an end-to-end technique and atraumatic sutures should be used, preferably 3-0 sutures.
Consensus-based recommendation 4.E11
Expert consensus
Level of consensus +++
If the ends of the internal anal sphincter can be identified, the edges must be approximated and sutured using atraumatic interrupted mattress sutures, preferably 3-0
sutures.
Consensus-based recommendation 4.E12
Expert consensus
Level of consensus +++
The end-to-end technique should be used if the external anal sphincter has not torn completely.
Consensus-based recommendation 4.E13
Expert consensus
Level of consensus +++
Neither the end-to-end technique nor the overlapping technique has been found to result in better outcomes following the repair of tears of the external anal sphincter. The
surgeon must therefore use the method with which he/she is most familiar.
5 The postpartum period
Consensus-based recommendation 5.E14
Expert consensus
Level of consensus +++
There is no evidence supporting the prophylactic postoperative administration of antibiotics. Postoperative doses of antibiotics may be recommended in selected cases after an
individual risk assessment which also takes local contamination and any potentially serious consequences into account.
Consensus-based recommendation 5.E15
Expert consensus
Level of consensus +++
Laxatives should be administered for a period of at least 2 weeks postoperatively.
Consensus-based recommendation 5.E16
Expert consensus
Level of consensus +++
Daily cleaning with running water is recommended, particularly after a bowel movement. Washing can be carried out by rinsing the area or using alternate cold and hot water
douches.
Consensus-based recommendation 5.E17
Expert consensus
Level of consensus +++
Sitz baths (with or without additives) and ointments should not be used.
Consensus-based recommendation 5.E18
Expert consensus
Level of consensus +++
Cool pads or cool topical analgesic medication should be used as it may reduce the swelling and thereby have a positive impact on pain.
Consensus-based recommendation 5.E19
Expert consensus
Level of consensus +++
It is important to ensure that pain therapy is adequate as local pain could lead to urinary and even fecal retention.
Consensus-based recommendation 5.E20
Expert consensus
Level of consensus +++
No rectal examination should be carried out in cases where the postpartum healing process is uncomplicated.
Consensus-based recommendation 5.E21
Expert consensus
Level of consensus +++
Patients must be informed about the extent of their birth trauma and potential late sequelae. The information must also include information about follow-up care, the actions they
should take, and the help that is available.
Patients must be informed about the possibility of a longer latency period until the appearance of symptoms of anal incontinence.
5.1 Antibiotics
There is only indirect evidence about the benefit of extended postoperative prophylactic administration of antibiotics [58 ]. Extended antibiotic
prophylaxis (e.g., cephalosporin + metronidazole for 5 days) may be administered after weighing up the risks in each individual case [36 ].
5.2 Laxatives
The postoperative use of laxatives is recommended (for pain reduction and to obtain a better functional outcome) [58 ], [59 ]. The authors of the guideline recommend the administration of laxatives for a period of at least 2 weeks postoperatively. No laxative therapy should be prescribed if the patient
is suffering from diarrhea.
5.2 Pain therapy and local therapy
Daily cleaning using running water of drinking water quality is recommended, particularly after a bowel movement (e.g., alternating cold and warm douches). There is no evidence supporting
the utility of sitz baths with or without additives or the use of wound ointments with special additives.
Cool compresses or cool topical analgesic medication may reduce the swelling and thereby have a positive impact on pain [60 ].
It is important to ensure that pain therapy is adequate as local pain could lead to urinary or even fecal retention [61 ].
No rectal examination should be carried out in cases where the postpartum healing process is uncomplicated [50 ].
The rate of wound complications after 3rd or 4th degree perineal tears (wound infection, dehiscence, repeat surgery, re-admission to hospital) is between 7.3% [62 ] and 24.6% [63 ]; smoking and a higher BMI are known to be independent risk factors while antibiotic therapy intrapartum reduces the risk of wound
healing disorders [62 ], [63 ].
Patients must be informed about the extent of their birth injury as well as potential late sequelae. Patients must be provided with sufficient information about follow-up care, the
actions they should take and the help that is available.
6 Follow-up care
Consensus-based recommendation 6.E22
Expert consensus
Level of consensus +++
A gynecological or coloproctological follow-up examination should be carried out after about 3 months and must include a review of the patientʼs medical history, symptoms of anal
incontinence, an inspection of the area, and vaginal and rectal palpation.
Consensus-based recommendation 6.E23
Expert consensus
Level of consensus +++
Patients should be referred to physiotherapy to strengthen their pelvic floor musculature.
Consensus-based recommendation 6.E24
Expert consensus
Level of consensus +++
If symptoms of anal incontinence persist despite carrying out all conservative treatment options, the patient must be referred to a center with the appropriate expertise (anal
endosonography, conservative and surgical treatment options).
A gynecological follow-up examination should be carried out around 3 months postpartum. The follow-up examination must at least include the following:
Review of the patientʼs medical history including questions about the following symptoms of anal incontinence. The incidences of the various symptoms reported at early follow-up
examinations after 3rd or 4th degree perineal tears are given in brackets [52 ], [57 ], [64 ] – [67 ]
flatulence incontinence (up to 50%)
fecal urgency (26%)
liquid stool incontinence (8%)
solid stool incontinence (4%)
Inspection of the affected area
Vaginal and rectal palpation
Referral of the patient to physiotherapy to strengthen her pelvic floor musculature. Early biofeedback-supported physiotherapy offers no advantages compared to classic pelvic floor
training [68 ]. In cases with anal incontinence, triple-target therapy (a combination of amplitude modulated medium frequency stimulation and
electromyography biofeedback) has been found to offer superior results compared to standard stimulation therapy with electromyography biofeedback [69 ].
The patient must be informed about the potential long latency period until the occurrence/worsening of symptoms of anal incontinence [7 ], [70 ].
Counselling with regard to subsequent deliveries
If the patient continues to have symptoms of anal incontinence, she should be referred to a center with the appropriate expertise (anal endosonography, conservative and surgical
treatment options).
7 Recommendations for subsequent births
Consensus-based recommendation 7.E25
Expert consensus
Level of consensus +++
Women who have a 3rd or 4th degree perineal tear should be offered an elective caesarean section, especially women with persistent symptoms of anal incontinence, reduced sphincter
function or suspected fetal macrosomia.
Consensus-based recommendation 7.E26
Expert consensus
Level of consensus +++
Women wishing to have a spontaneous vaginal birth must be carefully evaluated with regard to their history of potential sequelae of a previous 3rd or 4th degree perineal injury
and be informed in detail about the potential risks.
Consensus-based recommendation 7.E27
Expert consensus
Level of consensus +++
The indications for an episiotomy in a woman wishing to have a subsequent pregnancy with a vaginal birth after a previous 3rd or 4th degree perineal tear must very
restrictive.
The existing data does not permit any clear recommendations as to the birth mode in future pregnancies. The patient must be informed that, depending on the data source, the risk of a repeat
injury to the anal sphincter in a subsequent vaginal birth ranges from non-existent [45 ], [54 ], [55 ] to a sevenfold higher risk [71 ], [72 ], [73 ], [74 ], [75 ]; however, more than 95% of women do not suffer a repeat high-grade perineal tear [73 ], [76 ].
The risk of perineal laceration increases with increasing birth weight of the baby [71 ], [72 ], [73 ], [74 ], [75 ], [76 ]. It has also been shown that in vaginal births after a previous
3rd or 4th degree perineal tear, the short-term risk of persistent fecal incontinence is higher [77 ], [78 ]. The difference was
no longer found in long-term studies which covered a period of 5 or more years [79 ], [80 ].
Elective caesarean section should be offered to all women who have previously had a grade 3 or grade 4 perineal tear, particularly patients with persistent symptoms of fecal incontinence,
reduced sphincter function or suspected fetal macrosomia.
An episiotomy must be carried out restrictively if a woman wishes to have a vaginal delivery in a subsequent pregnancy after a prior 3rd or 4th degree perineal tear [76 ].
The following approach must be used if the patient wishes to have a vaginal delivery:
Good communication with the patient
Perineal “hands-on” support to ensure optimal control of the birth and gradual delivery of the babyʼs head
Slow delivery of the babyʼs head
The patient may freely choose the position in which she gives birth; however, once the baby is crowning, the perineal area must be clearly visible
A mediolateral episiotomy should be performed if required in individual cases [81 ]
