Effect of subsequent vaginal delivery on bowel symptoms and anorectal function in women who sustained a previous obstetric anal sphincter injury

Caesarean section and anal incontinence in women after obstetric anal sphincter injury: A systematic review and meta-analysis

BACKGROUND

Approximately 50% women who give birth after obstetric anal sphincter injury (OASI) develop anal incontinence (AI) over their lifetime.

OBJECTIVE

To evaluate current evidence for a protective benefit of planned caesarean section (CS) to prevent AI after OASI.

SEARCH STRATEGY

MEDLINE/PubMed, Embase 1974-2024, CINAHL and Cochrane to 7 February 2024 (PROSPERO CRD42022372442).

SELECTION CRITERIA

All studies reporting outcomes after OASI and a subsequent birth, by any mode.

DATA COLLECTION AND ANALYSIS

Eighty-six of 2646 screened studies met inclusion criteria, with nine studies suitable to meta-analyse the primary outcome of 'adjusted AI' after OASI and subsequent birth. Subgroups: short-term AI, long-term AI, AI in asymptomatic women.

SECONDARY OUTCOMES

total AI, quality of life, satisfaction/regret, solid/liquid/flatal incontinence, faecal urgency, AI in women with and without subsequent birth, change in AI pre- to post- subsequent birth.

MAIN RESULTS

There was no evidence of a difference in adjusted AI after subsequent vaginal birth compared with CS after OASI across all time periods (OR = 0.92, 95% CI 0.72-1.20; 9 studies, 2104 participants, I2 = 0% p = 0.58), for subgroup analyses or secondary outcomes. There was no evidence of a difference in AI in women with or without subsequent birth (OR = 1.00 95% CI 0.65-1.54; 10 studies, 970 participants, I2 = 35% p = 0.99), or pre- to post- subsequent birth (OR = 0.79 95% CI 0.51-1.25; 13 studies, 5496 participants, I2 = 73% p = 0.31).

CONCLUSIONS

Due to low evidence quality, we are unable to determine whether planned caesarean is protective against AI after OASI. Higher quality evidence is required to guide personalised decision-making for asymptomatic women and to determine the effect of subsequent birth mode on long-term AI outcomes.

UK survey of colorectal surgeons on the management of acute obstetric anal sphincter injuries

AIM

The role of colorectal surgeons in the management of acute obstetric anal sphincter injury (OASI) is an ongoing debate. Their expertise in operating in the anorectal region lends itself to assisting in OASI repair. The aim of this study was to establish the current involvement and recommended management of acute OASI by colorectal surgeons.

METHOD

An online survey of consultant colorectal surgeons was sent to members of the Pelvic Floor Society to assess current involvement in acute OASI management and repair.

RESULTS

Forty completed surveys were collated and analysed. Sixty-five per cent of respondents had seen an acute OASI since being a consultant and 50% stated they were involved in the repair of OASI less than once per year. 37.5% felt that a de-functioning stoma was still necessary sometimes. Many agreed with current guidelines for OASI repair in terms of antibiotics, laxatives and follow-up.

CONCLUSIONS

Colorectal surgeons have varied opinions on the management of OASI. We suggest that multidisciplinary training of obstetricians and colorectal surgeons could lead to more collaboration regarding the management of women with acute OASI.

Anal incontinence following obstetric anal sphincter injury: Is there a difference between subtypes? A systematic review

AIMS

Obstetric anal sphincter injury (OASI) is associated with long-term anal incontinence (AI). We aimed to address the following questions: (a) are women with major OASI (grade 3c and 4) at higher risk of developing AI when compared to women with minor OASI (grade 3a and 3b)? (b) is a fourth-degree tear more likely to cause AI over a third-degree tear?

METHODS

A systematic literature search from inception until September 2022. We considered prospective and retrospective cohort studies, cross-sectional and case-control studies without language restrictions. The quality was assessed by the Newcastle-Ottawa Scale and the Joanna Briggs Institute critical appraisal checklist. Risk ratios (RRs) were calculated to measure the effect of different grades of OASI.

RESULTS

Out of 22 studies, 8 were prospective cohort, 8 were retrospective cohort, and 6 were cross-sectional studies. Length of follow-up ranged from 1 month to 23 years, with the majority of the reports (n = 16) analysing data within 12-months postpartum. Third-degree tears evaluated were 6454 versus 764 fourth-degree tears. The risk of bias was low in 3, medium in 14 and high in 5 studies, respectively. Prospective studies showed that major tears are associated with a twofold risk of AI for major tears versus minor tears, while retrospective studies consistently showed a risk of fecal incontinence (FI) which was two- to fourfold higher. Prospective studies showed a trend toward worsening AI symptoms for fourth-degree tears, but this failed to reach statistical significance. Cross-sectional studies with long-term (≥5 years) follow-up showed that women with fourth-degree tear were more likely to develop AI, with an RR ranging from 1.4 to 2.2. Out of 3, 2 retrospective studies showed similar findings, but the follow-up was significantly shorter (≤1 year). Contrasting results were noted for FI rates, as only 5 out of 10 studies supported an association between fourth-degree tear and FI.

CONCLUSIONS

Most studies investigate bowel symptoms within few months from delivery. Data heterogeneity hindered a meaningful synthesis. Prospective cohort studies with adequate power and long-term follow-up should be performed to evaluate the risk of AI for each OASI subtype.

Follow up of women after obstetric anal sphincter injuries (OASI)-What is the role of anorectal testing?

AIMS

To evaluate the benefit of performing anorectal studies on all women following primary obstetric anal sphincter injury (OASI) repair over performing them on symptomatic women only.

METHODS

Women who attended perineal clinic between 2007 and 2020 underwent symptom assessment and anorectal studies at 6 weeks and 6 months postpartum. Anorectal studies including endo anal ultrasound (EAUS) and anal manometry (AM) were performed. The anorectal studies of symptomatic women who were the case group, were compared with asymptomatic women who were the control group.

RESULTS

A total of 1348 women were seen in the perineal clinic over 13 years. A total of 454 (33.7%) women were symptomatic. A total of 894 (66.3%) women were asymptomatic. A total of 313 (35%) asymptomatic women had two abnormal anorectal studies, 274 (31%) had abnormal AM alone, and 86 (9.6%) had abnormal EAUS alone. A total of 221 (24.7%) asymptomatic women had normal anorectal studies.

CONCLUSION

Almost 70% of women were asymptomatic 6 months following primary OASI repair. Most had at least one abnormal anorectal study result. Selectively performing anorectal tests on symptomatic women would not identify asymptomatic women at risk of future faecal incontinence following further vaginal birth. Without anorectal study results, women would not receive accurate counseling about the risks of vaginal birth. Anorectal studies should be offered to all women following OASI where resources allow.

Association of delivery mode and number of pregnancies with anorectal manometry data in patients with postpartum constipation

OBJECTIVE

To explore the association of delivery mode and the number of pregnancies with anorectal manometry data in patients with postpartum constipation.

METHODS

This retrospective study included women with postpartum constipation treated at the pelvic floor rehabilitation department of Huzhou Maternity & Child Health Care Hospital between January 2018 and December 2019.

RESULTS

Among 127 patients included, 55 (43.3%) had one pregnancy, 72 (56.7%) had two pregnancies, 96 (75.6%) delivered spontaneously, 25 (16.7%) underwent Cesarean section, and six (4.7%) needed a Cesarean section despite spontaneous labor. The median duration of constipation was 12 months (range, 6-12). There were no differences between the two groups for any manometry parameters (all P > 0.05). The patients with a spontaneous delivery had a lower change in maximal contracting sphincter pressure compared with those with Cesarean section (14.3 (4.5-25.0) vs. 19.6 (13.4-40.0), P = 0.023). Only the delivery mode (Cesarean vs. spontaneous) independently affected the changes in contracting sphincter pressure (B = 10.32, 95%CI: 2.95-17.69, P = 0.006); age (P = 0.201), number of pregnancies (P = 0.190), and constipation duration (P = 0.161) were not associated.

CONCLUSION

The patients with a spontaneous delivery had a lower change in maximal contracting sphincter pressure compared with those with a Cesarean section, suggesting that patients with Cesarean may retain a better "push" function during defecation.

Risk Factors for Anal Continence Impairment Following a Second Delivery after a First Traumatic Delivery: A Prospective Cohort Study

Postpartum anal incontinence is common. After a first delivery (D1) with perineal trauma, follow-up is advised to reduce the risk of anal incontinence. Endoanal sonography (EAS) may be considered to evaluate the sphincter and in case of sphincter lesions to discuss cesarean section for the second delivery (D2). Our objective was to study the risk factors for anal continence impairment following D2. Women with a history of traumatic D1 were followed before and 6 months after D2. Continence was measured using the Vaizey score. An increase ≥2 points after D2 defined a significant deterioration. A total of 312 women were followed and 67 (21%) had worse anal continence after D2. The main risk factors for this deterioration were the presence of urinary incontinence and the combined use of instruments and episiotomy during D2 (OR 5.12, 95% CI 1.22-21.5). After D1, 192 women (61.5%) had a sphincter rupture revealed by EAS, whereas it was diagnosed clinically in only 48 (15.7%). However, neither clinically undiagnosed ruptures nor severe ruptures were associated with an increased risk of continence deterioration after D2, and cesarean section did not protect against it. One woman out of five in this population had anal continence impairment after D2. The main risk factor was instrumental delivery. Caesarean section was not protective. Although EAS enabled the diagnosis of clinically-missed sphincter ruptures, these were not associated with continence impairment. Anal incontinence should be systematically screened in patients presenting urinary incontinence after D2 as they are frequently associated.

Mode of delivery following obstetric anal sphincter injury: a 7-year retrospective review and follow-up cohort survey

INTRODUCTION AND HYPOTHESIS

Limited evidence exists regarding long-term outcomes following birth after prior obstetric anal sphincter injury (OASI). This article set out to describe outcomes following birth after OASI by reviewing the grades of tear, endoanal ultrasound (EAUS) findings, subsequent delivery outcomes and long-term symptoms.

METHODS

This study was conducted in two parts. The first involved a retrospective review of all OASI at a tertiary hospital in Australia over 7 years (2013-2019 inclusive) where the patient underwent a subsequent delivery. Following this, a retrospective cohort survey of this group was performed.

RESULTS

There were 27,284 vaginal births and 828 OASIs (3.03%); 247 (29.8%) had at least one subsequent birth by January 2021. Vaginal delivery occurred in 68%; recurrence of OASI was 5.4%. There were 90 responses (36.4%) to the follow-up survey. EAUS had been performed in 87.5%; none demonstrated a defect. Vaginal birth was the preferred mode for 77.8%; this occurred in 64%. The majority had high levels of satisfaction, this related to communication rather than the mode of delivery itself. Ongoing faecal or flatal incontinence was reported by 12%. There was no statistically significant difference in St Mark's incontinence scores between modes of birth.

CONCLUSIONS

In our unit most women who sustain OASI will have a subsequent vaginal delivery in future pregnancies. The majority remain asymptomatic at long-term follow-up with no statistically significant difference in incontinence scores regardless of mode of delivery. The rate of recurrent OASI was 5.4%.

Comparison of diagnostic criteria for significant anal sphincter defects between endoanal and transperineal ultrasound

OBJECTIVE

To evaluate the agreement between three-dimensional endoanal ultrasound (EAUS) and four-dimensional transperineal ultrasound (TPUS) in measuring anal sphincter defect angle.

METHODS

This was a secondary analysis of the PERINEAL study, which evaluated the effect of perineal wound infection on anal sphincter integrity. Women were reviewed once a week, until their perineal wound had healed or for up to a maximum of 16 weeks. At each visit, both EAUS and TPUS (the latter at rest and on maximum pelvic floor muscle contraction (PFMC)) were performed to evaluate the presence of external (EAS) and internal (IAS) anal sphincter defect and measure the defect size. The largest angle size of a defect at the same sphincter level was analyzed. A defect was deemed significant if it was > 30°. Kappa coefficient (κ), intraclass correlation coefficient and standard error of measurement (SEM) were calculated, using EAUS as the reference standard.

RESULTS

In 73 women scanned at weekly intervals, a total of 250 EAUS and 250 TPUS scans were performed. An EAS defect was found in 55 (22.0%) EAUS images and 47 (18.8%) TPUS images. An IAS defect was found in 26 (10.4%) images on both modalities. There was excellent agreement (κ = 0.87) between TPUS and EAUS in diagnosing the presence of an EAS defect and perfect agreement (κ = 1.00) in diagnosing the presence of an IAS defect. TPUS performed at rest had poor and moderate agreement with EAUS in measuring EAS and IAS defect size, respectively, with respective SEMs of ± 16.1° and ± 27.9°. TPUS performed during maximum PFMC had poor and moderate agreement with EAUS in measuring EAS and IAS defect size, respectively, with respective SEMs of ± 16.5° and ± 26.4°. Based on the SEMs, if the diagnostic cut-off of 30° for defect size on TPUS was used, an incorrect diagnosis of significant EAS defect could occur in approximately 9-36% of women and an incorrect diagnosis of a significant IAS defect could occur in approximately 4-15% of women, using EAUS as the reference.

CONCLUSIONS

This is the first study to compare directly anal sphincter defect angle measurements obtained on EAUS and TPUS. A cut-off angle of 30° should not be used for the diagnosis of a significant residual anal sphincter defect during TPUS examination. Further research is required to determine the optimal defect cut-off angle for TPUS. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Anal endosonographic assessment of the accuracy of clinical diagnosis of obstetric anal sphincter injury

INTRODUCTION AND HYPOTHESIS

Obstetric anal sphincter injuries (OASIS) are a common cause of maternal morbidity with an overall incidence in the UK of 2.9% (range 0-8%). They can cause a range of physical symptoms and psychological distress. This study aims to assess the accuracy of clinical diagnosis of OASIS using endoanal ultrasound (EAUS) and the correlation between confirmed injury and change to anorectal physiology squeeze pressure and the incidence of bowel symptoms.

METHODS AND MATERIALS

Retrospective study of prospectively collected data from 1135 women who attended the Third- and Fourth-Degree Tears Clinic at our institution, 12 weeks post-delivery, between June 2008 and October 2019.

RESULTS

OASIS was confirmed in 876 (78.8%) women and 236 (21.3%) had no injury. Of the women who underwent anorectal physiology, 45.6% had a mean maximal resting pressure below the normal range and 68.8% had a mean incremental squeeze pressure below normal. Women with confirmed OASIS had significantly lower pressures (p < 0.001) than those without a confirmed sphincter injury. Three hundred ninety-three (34.8%) women reported bowel symptoms, with those with endosonographic evidence of injury more likely to develop flatus incontinence.

CONCLUSION

Of the women in this study with a suspected OASIS, 21.2% could be reassured that they did not have an injury. This information is useful for women considering future mode of delivery. Those with confirmed injury are more likely to complain of flatus incontinence and have reduced anal sphincter pressures.

Faecal incontinence in adults

Faecal incontinence, which is defined by the unintentional loss of solid or liquid stool, has a worldwide prevalence of ≤7% in community-dwelling adults and can markedly impair quality of life. Nonetheless, many patients might not volunteer the symptom owing to embarrassment. Bowel disturbances, particularly diarrhoea, anal sphincter trauma (obstetrical injury or previous surgery), rectal urgency and burden of chronic illness are the main risk factors for faecal incontinence; others include neurological disorders, inflammatory bowel disease and pelvic floor anatomical disturbances. Faecal incontinence is classified by its type (urge, passive or combined), aetiology (anorectal disturbance, bowel symptoms or both) and severity, which is derived from the frequency, volume, consistency and nature (urge or passive) of stool leakage. Guided by the clinical features, diagnostic tests and therapies are implemented stepwise. When simple measures (for example, bowel modifiers such as fibre supplements, laxatives and anti-diarrhoeal agents) fail, anorectal manometry and other tests (endoanal imaging, defecography, rectal compliance and sensation, and anal neurophysiological tests) are performed as necessary. Non-surgical options (diet and lifestyle modification, behavioural measures, including biofeedback therapy, pharmacotherapy for constipation or diarrhoea, and anal or vaginal barrier devices) are often effective, especially in patients with mild faecal incontinence. Thereafter, perianal bulking agents, sacral neuromodulation and other surgeries may be considered when necessary.

Three-Dimensional Ultrasound Imaging under Optimized Nuclear Regression Reconstruction Algorithm in the Diagnosis Vaginal Delivery and Cesarean Section on the Anal Sphincter Complex of Primiparas

This study was aimed at analyzing the injury of anal sphincter (AS) for primipara caused by the vaginal delivery and cesarean section under the guidance of three-dimensional (3D) ultrasound images. A total of 160 patients who underwent postpartum reexamination were enrolled as the research subjects, including 80 cases of natural delivery (group A) and 80 cases of cesarean section pregnant women (group B), all of whom underwent three-dimensional ultrasound imaging scans. At the same time, an optimized kernel regression reconstruction (KRR) algorithm was proposed for the enhancement of ultrasound images. It was found that the running time after acceleration by the graphics processing unit (GPU) was obviously superior to that of a single-threaded CPU and a multithreaded CPU, showing statistical differences (P < 0.05). The thickness of the proximal and distal external AS in group A was much thinner in contrast to that in group B, showing statistical difference (P < 0.05). Therefore, the 3D ultrasound image based on the optimized KRR algorithm can accurately assess the morphology of AS injury in primipara, and the adverse effect of natural delivery on the AS complex in primipara was greater than that of cesarean section.

Is there a role for transperineal ultrasound imaging of the anal sphincter immediately after primary repair of third degree tears?

OBJECTIVE

When obstetric anal sphincter injuries are identified, it is crucial that the defects are repaired appropriately to achieve a better outcome. Although the presence of an intact anal sphincter is not the sole mechanism for maintaining continence, and not all women with an anal sphincter defect are symptomatic, there is an association between sphincter defects and anal incontinence. Our aim was to evaluate whether transperineal ultrasound (TPUS) is useful in assessing anal sphincter integrity immediately following primary repair of obstetric anal sphincter injuries (OASIs).

STUDY DESIGN

This is a prospective observational study of women who sustained OASIs during their first vaginal delivery. Three dimensional (3D) TPUS was performed immediately after repair of OASIs to identify anal sphincter defects. A repeat TPUS was performed 12 weeks following repair.

RESULTS

21 women sustained OASIs of whom 20 (95%) attended follow up. Eight (40%) had a grade 3a tear and 12 (60%) a 3b tear. 8/20 (40%) women had residual external anal sphincter (EAS) defects identified by TPUS immediately after repair. Of these eight defects, six (75%) persisted at 12 weeks postpartum. No new defects were seen at follow up among the twelve women in whom no defect was seen immediately following the repair. Six residual EAS defects were found at 12 weeks postpartum. An EAS defect at 12 weeks postpartum was associated with anal incontinence (p = 0.04). Women with 3b tears were more likely to have anal incontinence (AI) and residual sonographic EAS defects when compared with 3a tears but this was not statistically significant.

CONCLUSIONS

Women who had no TPUS defect detected immediately following primary repair of OASIs, remained as such at 12 weeks postpartum. Of those in whom a defect was seen immediately after repair, it persisted in 75% of cases at 12 weeks. We believe that the value of TPUS immediately after repair appears to be limited and would need to be defined if it were to be considered for routine practice. Further research on its role immediately after repair of major tears (Grade 3C/4) is needed. In addition, performing ultrasound would require widespread training of obstetricians to develop expertise. This highlights the importance of adequate training of obstetricians in OASI repair.

Surgical repair and follow-up of chronic 4th degree obstetric perineal tear (total perineal defect) in 2 centres in eastern Africa

Introduction and hypothesis

Fourth-degree perineal tear occurs in up to 0.2% of vaginal deliveries. In limited resource communities, women often deliver in local villages without facilities to repair obstetric anal sphincter injuries. These fourth-degree tears heal by secondary intention and result in total perineal defects. The aim of the study is to present medium-term follow-up of a large number of women following repair of chronic fourth-degree tear.

Methods

Repairs of chronic obstetric fourth-degree tears were undertaken during surgical camps at Kagando Hospital, Uganda and Selian Hospital, Tanzania, from December 2013 to October 2019. Women completed Cleveland Clinic Incontinence Scores (CCIS) on admission (face to face) and during the 7-year follow-up period (via telephone).

Results

Two hundred fourteen women had medical history and CCIS completed on admission. The mean age at presentation was 33.9 years and mean duration of the condition was 8.9 years. Over a third of women stated they suffered social abandonment because of the unrepaired fourth-degree tear. Nearly 45% of women suffered the tear during the first vaginal delivery. At 1-year follow-up, 87% of 101 women scored 0 (perfect continence) and 94% of 66 women had perfect continence at 2 years. Forty-one births occurred during the follow-up period (32 vaginal deliveries) with two recurrences of fourth-degree tear.

Conclusions

Follow-up in limited resource communities is challenging. Short- to medium-term results of women who had repair of total perineal defect (unrepaired fourth-degree obstetric tears) are encouraging.

Early secondary repair of obstetric anal sphincter injuries (OASIs): experience and a review of the literature

INTRODUCTION AND HYPOTHESIS

Secondary anal sphincter repair for a dehisced obstetric anal sphincter injury (OASI) is required following 2.6% of primary repairs. There is growing evidence that instead of delaying repair for 3-6 months, early secondary repair of the anal sphincter can be completed within 14 days. Our aims were to review the literature and to describe experiences in our unit.

METHODS

This is a narrative review of all published cases reporting outcomes of early secondary repair of dehisced OASIs. In addition, we report a series from Croydon University Hospital (CUH) between 2010 and 2019.

RESULTS

Ninety patients from five studies were identified on literature search. Six patients from CUH were included in the case series. Overall, the most common complications following secondary repair included skin dehiscence [10.3% (n = 10)], infection [5.2% (n = 5)] and fistula formation [8.2% (n = 8)]. In our case series, following secondary repair, normal manometric incremental squeeze pressure was found in five women (83%). Also, on endoanal ultrasound, internal anal sphincter (IAS) defects were found in 75% with a history of IAS injury (n = 4). There were no full-thickness external anal sphincter defects. Compared to those requiring primary repair alone, residual defects were significantly larger in those who also underwent secondary repair (Starck score 2.1 vs. 5.7, p = 0.01).

CONCLUSION

Early secondary repair is a feasible surgical procedure for the reconstruction of dehisced OASIs. This case series and review of the literature can be used to support clinicians in the management of primary OASI repair dehiscence.

Establishing a peripartum perineal trauma clinic: a narrative review

INTRODUCTION AND HYPOTHESIS

Obstetric anal sphincter injury (OASI) is not rare, and its consequences are multiple and potentially severe, especially for young women. Some dedicated perineal clinics have been established to improve the management of OASI. Despite their obvious importance, these specific clinics are underrepresented and underdeveloped. The objectives of this review are to explore various options for developing a peripartum perineal clinic and to compare the different practices regarding the mode of delivery for subsequent pregnancies after an OASI.

METHODS

This narrative review covers information from patients' questionnaires specific to anal incontinence, anal physiology assessment, pelvic floor and anal sphincter imaging, and the arguments for choosing the mode of delivery after an OASI.

RESULTS

This review highlights the extensive range of practices regarding the delivery mode after an OASI throughout national professional organizations and experienced perineal clinics.

CONCLUSION

This review summarizes the different choices in developing a perineal clinic to facilitate their development in promoting health care and education specific for peripartum women concerning the perineal consequences of delivery for obstetrician-gynaecologists, family doctors, and residents.

Effect of a subsequent pregnancy on anal sphincter integrity and function after obstetric anal sphincter injury (OASI)

Introduction and hypothesis

Endoanal ultrasound (EAUS) and anal manometry are used in the assessment women with a history of obstetric anal sphincter injury (OASI), both postpartum and in a subsequent pregnancy, to aid counselling regarding mode of delivery (MOD).

Methods

A prospective observational study between 2012 to 2020 was completed. Women were reviewed 3 months postpartum following OASI and in the second half of a subsequent pregnancy. Anorectal symptoms were measured using the validated St Mark’s Incontinence Score (SMIS: asymptomatic to mild symptoms = ≤ 4). Anal manometry (incremental maximum squeeze pressure [iMSP: normal = > 20 mmHg]) and EAUS (abnormal = sphincter defect > 1 h in size) were performed.

Results

One hundred forty-six women were identified and 67.8% had an anal sphincter defect ≤ 1 h in size postnatally. In those with a defect ≤ 1 h, postpartum mean iMSP and SMIS significantly improved in a subsequent pregnancy (p = 0.04 and p = 0.01, respectively). In women with a defect > 1 h, there was no significant difference between the mean iMSP or SMIS score postnatally compared to a subsequent pregnancy. At both time points, significantly more women had an anal sphincter defect ≤ 1 h and SMIS of ≤ 4 (p = 0.001 and p < 0.001 respectively) compared to those with a defect < 1 h. In addition, significantly more women had an anal sphincter defect ≤ 1 h and iMSP ≥ 20 mmHg (p < 0.001). Overall, out of the 146 women included in this study, 76 (52.1%) with a defect ≤ 1 h also had an iMSP ≥ 20 mmHg and SMIS ≤ 4 at 3 months postpartum.

Conclusions

Women who remain asymptomatic with normal anal manometry and no abnormal sphincter defects on EAUS postnatally do not need to have these investigations repeated in a subsequent pregnancy and can be recommended to have a vaginal delivery. If our protocol was modified, over half of the women in this study could have had their MOD recommendation made in the postnatal period alone.

Management of obstetric anal sphincter injury: Colorectal surgeons' perspectives in Australia and New Zealand

BACKGROUND

Obstetric anal sphincter injuries (OASIs) are a significant complication of vaginal delivery, and a leading cause of anal incontinence in women.

AIMS

The aims were to explore the management of OASIs in Australia and New Zealand (ANZ) by colorectal surgeons and how this compares with current recommendations and international experience, and to identify the deterrents to the provision of best-practice care among colorectal surgeons.

MATERIALS AND METHODS

Three hundred colorectal surgeons of the Colorectal Surgical Society of ANZ were mailed questionnaires. Areas of interest included: surgeon demographics; exposure to OASIs; understanding of current recommendations; and opinions regarding the importance of symptoms and assessment tools in OASIs.

RESULTS

There were 94 completed questionnaires (response rate 31.3%). Fifty-seven surgeons (60.6%) reported low exposure to OASIs during their fellowship training. Greater than 90% believed patients with grade three tears and above should have anal sphincter assessment. Sixty-six (70.2%) reported that they routinely review women who have had OASIs. However, 56.4% were unaware if their obstetrics department followed a standard protocol for OASIs. Surgeons practising in metropolitan centres reported higher rates of their obstetrics department following a protocol (P = 0.013), and greater access to investigative tools (P < 0.001), when compared to rural-based surgeons.

CONCLUSIONS

Most ANZ colorectal surgeons have had minimal training in OASI management. Colorectal surgeons are more commonly involved with OASI patients in the non-acute setting. Management protocols involving a multidisciplinary team of both colorectal surgeons and obstetricians should be clearly defined, and the gap between metropolitan and rural centres needs to be reviewed.

Isolated rectal buttonhole tears in obstetrics: case series and review of the literature

Introduction and hypothesis

The management of isolated rectal buttonhole tears is not standardised and can be challenging in an acute obstetric setting. Our aim was to review the published literature and describe management and repair techniques in a case series.

Methods

A literature search was carried out. All results were screened and reviewed. Rectal buttonhole tears following vaginal delivery between April 2012 and January 2020 in our institution were identified. Repair technique and post-operative management were recorded.

Results

There were nine published case reports (four instrumental deliveries, two vaginal breech and three normal vaginal deliveries). Four case reports described a two-layer closure and five described a three-layer closure. Two cases were repaired in collaboration with colorectal surgeons. All nine cases made an uneventful recovery. We identified three patients with buttonhole tears all of whom had instrumental deliveries. A colorectal surgeon repaired the tear in two layers in one case, and an obstetrician performed the repair in the other two cases, one in three layers and the other in two layers. One patient had a de-functioning stoma at a later date due to a second breakdown of the recto-vaginal fistula repair.

Conclusion

Buttonhole tears are rare but techniques of repair vary. Most cases reviewed had an uneventful recovery after repair. We provide standardised steps for repair and management of isolated rectal buttonhole tears along with a video demonstrating the repair technique in an animal tissue (pig) model.

Electronic supplementary material

The online version of this article (10.1007/s00192-020-04502-2) contains supplementary material, which is available to authorized users.

A one-stop perineal clinic: our eleven-year experience

Introduction and hypothesis

The perineal clinic is a dedicated setting offering assessment for various childbirth-related presentations including obstetric anal sphincter injuries (OASIs), perineal wound complications, pelvic floor dysfunction and other conditions such as female genital mutilation(FGM). We describe the clinical presentation and outcomes of women from a tertiary perineal clinic based on data collected over an 11-year period.

Methods

This is a retrospective observational study. A one-stop outpatient service was offered to all women who sustained OASIs (postnatally and antenatally in a subsequent pregnancy), perineal complications (within 16 weeks postpartum), FGM and/or peripartum symptoms of urinary/anal incontinence or prolapse. Assessment included history with validated questionnaires, examination and anal manometry and endoanal ultrasound when appropriate. Outcomes were compared among different grades of OASIs. Management of each type of presentation was reported with outcomes.

Results

There were 3254 first attendance episodes between 2006 and 2016. The majority (58.1%) were for OASIs, followed by perineal wound complications. Compared to the lower grades, the higher grades of OASI were associated with poorer outcomes in terms of symptoms, investigations and complications. Women with OASIs had unrelated symptoms such as urinary incontinence, perineal pain and wound infections that needed further intervention. A high proportion(42%) of wound complications required further specialist management.

Conclusion

We describe a dedicated, one-stop perineal clinic model for antenatal and postnatal women for management of perineal and pelvic floor disorders. This comprehensive and novel data will enable clinicians to better counsel women regarding of outcomes after OASI and focus training to minimize risks of morbidities.

Outcome of anal symptoms and anorectal function following two obstetric anal sphincter injuries (OASIS)-a nested case-controlled study

Introduction and hypothesis

Obstetric anal sphincter injury (OASI) is a significant risk factor for developing anal incontinence. It can therefore be hypothesised that recurrent OASI in a subsequent delivery may predispose women to further anal sphincter dysfunction.

Methods

A nested case-controlled study based on data collected prospectively between 2006 and 2019. Women matched for age and ethnicity, with a history of one OASI and no sphincter damage in a subsequent delivery (control) were compared to women sustaining a second OASI. Assessment was carried out using the St Mark’s score (SMIS), anorectal manometry and endoanal ultrasound scan (findings quantified using the modified Starck score).

Results

Eighty-four women were included and equally distributed between the two groups, who were followed up 12 weeks postnatally. No difference in SMIS scores was found. Maximum resting pressure (MRP, mmHg) and maximum squeeze pressure (MSP, mmHg) were significantly reduced in the study group. Median (IQR) MRP in the study group was 40.0 (31.3–54.0) versus 46.0 (39.3–61.5) in the control group (p = 0.030). Median (IQR) MSP was 73.0 (58.3–93.5) in the study group versus 92.5 (70.5–110.8) (p = 0.006) in the control group. A significant difference (p = 0.002) was found in the modified Starck score between the study group (median 0.0 [IQR 0.0–6.0]) and control group (median 0.0 [IQR 0.0–0.0]).

Conclusions

We have demonstrated that women with recurrent OASI do not have significant anorectal symptoms compared to those with one OASI 12 weeks after delivery, but worse anal sphincter function and integrity. Therefore, on long-term follow-up, symptoms may possibly develop. This information will be useful when counselling women in a subsequent pregnancy.

Management of subsequent pregnancies following fourth-degree obstetric anal sphincter injuries (OASIS)

OBJECTIVES

The management of subsequent pregnancy in women who sustained OASIS remains an enigma. Nearly all studies include all grades of OASIS including fourth-degree tears. In addition, most protocols require endoanal ultrasound and anal manometric assessment to provide advice regarding mode of delivery. In reality, most women who sustain an OASI do not undergo these investigations. The aims of our study were firstly to evaluate outcomes of fourth-degree OASIS in terms of sphincter defects, anal manometry and anal incontinence symptoms. Secondly, we wished to review recommendations made regarding subsequent mode of delivery after fourth-degree OASIS according to different published protocols.

STUDY DESIGN

An observational study of all women who had undergone a primary repair of a fourth-degree tear and seen in the perineal clinic of a tertiary urogynaecology unit between January 2006 and December 2017. Three-dimensional endoanal ultrasound and anal manometry were performed on all women, and symptoms assessed using the validated modified St Mark's Score for anal incontinence. Diagnostic test accuracy analysis was performed for use of symptoms in predicting abnormal investigations.

RESULTS

74 fourth-degree tears were identified (mean follow-up 5.9 months; SD 11.5). Endoanal scan showed an internal anal sphincter defect in 77 % and an external anal sphincter defect in 49 %. Only 18 % had no defect. The mean incremental pressure rise was 12.6 mmHg (SD 15.5). 61 % were asymptomatic with a mean St Mark's Score of 3.8 (SD 5.4). The presence of symptoms alone had poor accuracy in predicting abnormal investigations. Based on Royal College of Obstetricians and Gynaecologists guidance, only 7% would not be offered a caesarean section as they are asymptomatic women with normal scan and manometry findings and would be counselled for a vaginal delivery.

CONCLUSIONS

Given that only a few units offer these specialist investigations to their OASI population, it would be reasonable to offer caesarean section to all women who have sustained a fourth-degree tear. However, in centres where endoanal ultrasound and anal manometry are available, individualised counselling can be offered.

The impact of mode of subsequent birth after obstetric anal sphincter injury on bowel function and related quality of life: a cohort study

Introduction and hypothesis

The objective was to assess the impact of mode of subsequent birth on bowel function and related quality of life (QoL) in pregnant women with previous obstetric anal sphincter injury (OASI).

Methods

A prospective cohort study, designed, undertaken and reported using the Strengthening the Reporting of Observational Studies in Epidemiology statement and checklist. All pregnant women with previous OASI recruited at a specialist antenatal OASI clinic in a tertiary hospital to discuss mode of subsequent birth, between 1 January 2014 and 31 October 2015. Women are counselled in line with local guidelines based on Royal College of Obstetricians and Gynaecologists Green-top recommendations. In addition to routine endoanal ultrasound scan (EAUS), women recruited to the study were asked to complete the validated Manchester Health Questionnaire (MHQ) at both 34 weeks’ gestation and 6 months postnatally.

Results

Of the 175 study participants, 125 (71.4%) completed follow-up at 6 months. There was no significant change in frequency of bowel symptoms or QoL domain scores in women who had a subsequent vaginal birth compared with caesarean section. Multivariate analysis showed the odds of having poor “incontinence impact” (OR 2.91, 95% CI 1.03–8.21) and “physical limitations” (OR 4.56, 95% CI 1.02–20.45) were significantly higher for women who had a subsequent caesarean section.

Conclusions

For women with previous OASI, a subsequent vaginal birth is suitable for those with no bowel symptoms and normal EAUS and caesarean section is reasonable for women who do not have normal bowel function and/or normal EAUS findings; however, for some of these women bowel symptoms and QoL may be worsened.

Electronic supplementary material

The online version of this article (10.1007/s00192-020-04234-3) contains supplementary material, which is available to authorized users

Parturition mode recommendation and symptoms of pelvic floor disorders after obstetric anal sphincter injuries

INTRODUCTION AND HYPOTHESIS

Our primary objective was to evaluate parturition mode (PM) recommendations following obstetric anal sphincter injuries (OASIs) and adherence to these recommendations and to evaluate recurrence of OASIs in women who had a subsequent vaginal delivery (VD). The hypothesis was that adherence to the PM recommendations leads to a reasonable OASI recurrence rate.

METHODS

This was a retrospective observational cohort study of patients with previous OASIs between 2010 and 2016. After an outpatient visit including 3D transperineal ultrasound to screen for pelvic floor and anal sphincter injuries, all patients received recommendations for a subsequent PM. Patients were invited to complete validated questionnaires 2 to 5 years post-OASIs.

RESULTS

The majority of invited patients (265/320) attended follow-up, with 264 receiving a recommendation for PM. Only 5.6% did not adhere to the received recommendation. One hundred sixty-one patients delivered again, 58% had a VD, and 42% had a cesarean section (CS). Recurrence of OASIs was observed in 4.3% of the patients that had a VD. Fecal incontinence occurred in 4.9%, however any form of anal incontinence in 48% of patients. While dyspareunia was common in patients with residual external anal sphincter (EAS) injuries and levator ani muscle (LAM) avulsions, anal pain occurred more frequently in EAS injuries and fecal incontinence in LAM avulsions.

CONCLUSIONS

This study showed that the vast majority of patients followed PM recommendations, and this resulted in a low recurrence of OASIs with a high CS rate. Fecal incontinence after OASIs was correlated with the degree of OASIs.

Comparing the diagnostic accuracy of 3 ultrasound modalities for diagnosing obstetric anal sphincter injuries

BACKGROUND

The optimal imaging modality of obstetric anal sphincter injuries needs to take into consideration convenience, availability, and ability to assess the sphincter morphologic condition. Endoanal ultrasound imaging currently is regarded as the reference standard, but it is not widely available in obstetric units. Exoanal alternatives exist, such as 3-dimensional introital or transperineal ultrasound imaging, which are already readily available in most obstetrics and gynecology units.

OBJECTIVE

The primary objective was to evaluate the diagnostic accuracy of 3-dimensional introital and 3-dimensional transperineal ultrasound imaging compared with 3-dimensional endoanal ultrasound imaging as the reference standard for the detection of anal sphincter defects in women who sustained obstetric anal sphincter injuries. The secondary objective was to correlate a diagnosis of anal sphincter defect on imaging to symptoms of anal incontinence, and to assess patient discomfort that is experienced for each imaging modality.

STUDY DESIGN

A cross-sectional study was conducted of 250 women who sustained obstetric anal sphincter injuries, all of whom underwent 3-dimensional introital, transperineal, and endoanal ultrasound imaging. Introital and transperineal ultrasound imaging were assessed with tomographic ultrasound imaging. All of the women completed a validated modified St Mark's Score and Visual Analogue Score for discomfort. Optimal cut-off values for a significant defect on tomographic ultrasound imaging were defined as those with the greatest sensitivity and specificity based on receiver operating characteristic curves with endoanal ultrasound imaging as the reference standard. Diagnostic test characteristics of introital and transperineal ultrasound imaging were calculated with the use of these optimal cut-offs.

RESULTS

Optimal cut-off for a significant external anal sphincter defect was ≥3 of 7 slices; sensitivity and specificity were 0.65 and 0.75 on introital imaging and 0.70 and 0.69 on transperineal ultrasound imaging. Optimal cut-off for a significant internal anal sphincter defect was ≥2 of 5 slices; sensitivity and specificity were 0.59 and 0.84 on introital imaging and 0.43 and 0.97 on transperineal ultrasound imaging. The area under the curve for the diagnosis of external and internal anal sphincter defects ranged from 0.70-0.74 (P<.001) for introital and transperineal imaging. Positive predictive value for external and internal sphincter defects ranged from 0.37-0.63, and negative predictive value ranged from 0.85-0.93 for introital and transperineal ultrasound imaging. Endoanal ultrasound imaging was the only modality for a defect to correlate with symptoms; mean modified St. Mark's score for a defect sphincter was 2.4 (standard deviation, 4.1) and for an intact sphincter was 0.9 (standard deviation, 2.7; P<.01). Introital and transperineal ultrasound imaging were associated with less discomfort than endoanal ultrasound imaging.

CONCLUSION

Endoanal ultrasound imaging remains the most accurate diagnostic imaging modality. With low positive predictive values, introital and transperineal ultrasound imaging are not suitable for the identification of sphincter defects; however, high negative predictive values show a good ability to detect an intact sphincter. The optimal cut-off number of slices on tomographic ultrasound imaging for external and internal anal sphincters allows for standardization of a significant defect. In women with a history of obstetric anal sphincter injuries, introital and transperineal ultrasound imagings are suitable to screen for an intact sphincter if endoanal ultrasound imaging is not available. When defects are found, women should then have endoanal ultrasound imaging to verify the diagnosis.

The consequences of undiagnosed obstetric anal sphincter injuries (OASIS) following vaginal delivery

INTRODUCTION AND HYPOTHESIS

We aimed to compare anal and urinary incontinence symptoms and anal manometry between women with undiagnosed obstetric anal sphincter injuries (OASIS) and women who had OASIS diagnosed and repaired.

METHODS

This was a matched retrospective cohort study. Each missed OASI was matched with a diagnosed OASI for severity [minor (3a/b) or major (3c)], parity and length of follow-up. Women completed the modified St Mark's Incontinence Score and International Consultation on Incontinence Questionnaire. Women with OASIS or those without OASIS but with anal incontinence symptoms were seen in perineal clinic for perineal examinations, anorectal manometry and three-dimensional endoanal ultrasound 8-12 weeks postnatally or in a subsequent pregnancy.

RESULTS

Forty missed OASIS were matched with 40 recognised OASIS (16 3a/b; 24 3c). The median modified St Mark's scores were higher for missed tears [11 (4, 15) vs. 1 (0, 4), p < 0.001] as well as the urinary incontinence scores [4 (0, 6) vs. 0 (0, 2), p = 0.01] than for the control group. Missed OASIS patients had a shorter perineal body [1.6 ± 1.3 vs. 2.4 ± 0.8, p = 0.009]. All missed OASIS had larger defects on endoanal ultrasound. One in four missed OASIS required further surgery [aOR 4.1 (95% CI 1.0-16.3), p = 0.04] and almost all needed colorectal input [aOR 24.1 (95% CI 7.3-80.0), p < 0.0001]. There were no differences in anal manometry.

CONCLUSIONS

Women with symptomatic missed OASIS are compromised in terms of anal and urinary incontinence symptoms, sphincter defect size and perineal body size requiring additional colorectal input. This highlights the importance of preventing OASIS and perseverance with training to diagnose OASIS.

Maternal outcomes in subsequent delivery after previous obstetric anal sphincter injury (OASI): a multi-centre retrospective cohort study

Introduction and hypothesis

Women with a history of obstetric anal sphincter injury (OASI) are at increased risk of recurrence (rOASI) at subsequent delivery; however, evidence regarding the factors influencing this risk is limited. Furthermore, little is known about what factors influence the decision to alternatively deliver by elective caesarean section (ELLSCS).

Methods

Retrospective univariate and multivariate logistic regression analysis of prospectively collected data from four NHS electronic maternity databases including primiparous women sustaining OASIS during a singleton, term, cephalic, vaginal delivery between 2004 and 2015, who had a subsequent delivery.

Results

Two thousand two hundred seventy-two women met the criteria; 10.2% delivering vaginally had a repeat OASI and 59.4% had a second-degree tear. Women having an ELLSCS were more likely to be Caucasian, older, have previously had an operative vaginal delivery (OVD) and have a more severe degree of OASI. Positive predictors for rOASI were increased birth weight and maternal age at both index and subsequent deliveries, a more severe degree of initial OASI and Asian ethnicity. The overall mediolateral episiotomy (MLE) rate was 15.6%; 77.2% of those who had an episiotomy sustained no spontaneous perineal trauma. Only 4.4% of women with a rOASI had an MLE, whilst the MLE rate was 16.9% in those without a recurrence (p < 0.001). MLE decreased the risk of rOASI by 80%. Birth weight > 4 kg increased the risk 2.5 fold.

Conclusions

Women with previous OASIS are at an increased risk of recurrence. A more liberal use of MLE during subsequent vaginal delivery could significantly reduce the risk of recurrence.

Does flatus incontinence matter?

INTRODUCTION AND HYPOTHESIS

This study aimed to determine whether incontinence to flatus is associated with women's bother in a symptomatic population and with sonographically diagnosed external anal sphincter (EAS) trauma.

METHODS

This is a retrospective study of women attending a tertiary urogynecological unit between May 2013 and November 2015. Baseline evaluation included a standardized interview with St. Mark's Incontinence Score (SMIS) and visual analog scale (VAS) assessment for bother, as well as a physical examination and translabial pelvic floor ultrasound. At least one volume obtained covered the entire length of the EAS. These volumes were analyzed with the reviewer blinded to all clinical data.

RESULTS

During the inclusion period, 1104 patients visited the unit. Fifty-three patients were excluded from the study for missing data, leaving 1051 for final analysis. Mean age was 57 years (56-58) and mean body mass index (BMI) 29.1 kg/m² (28.8-29.6). The prevalence of any anal incontinence (AI) and flatus incontinence were 16.4% (172/1051) and 13.9% (146/1051), respectively. In the group of patients with AI, mean SMIS was 11.8 (11.0-12.6), and mean VAS for AI bother was 5.4 (5.0-5.9). Significant EAS trauma was detected in 9.8% (103/1051) of patients and was associated with flatus incontinence (p = 0.002). Including a flatus incontinence question in the SMIS questionnaire improved the prediction of patient bother from AI (R² 87.8% versus R² 86.3%, p = 0.04).

CONCLUSIONS

Flatus incontinence is associated with ultrasound findings of EAS trauma and with higher patient bother from AI.