A prospective study of anal sphincter injury due to childbirth

Predictive factors for obstetric anal sphincter injury in primiparous women: systematic review and meta-analysis

OBJECTIVES

The primary objective was to perform a systematic review of predictive factors for obstetric anal sphincter injury (OASI) occurrence at first vaginal delivery, with the diagnosis made by ultrasound (US-OASI). The secondary objective was to report on incidence rates of sonographic anal sphincter (AS) trauma, including trauma that was not clinically reported at childbirth, among the studies providing data for our primary objective.

METHODS

We conducted a systematic search of MEDLINE, EMBASE, Web of Science, CINAHL, The Cochrane Library and ClinicalTrials.gov databases. Both observational cohort studies and interventional trials were eligible for inclusion. Study eligibility was assessed independently by two authors. Random-effects meta-analyses were performed to pool effect estimates from studies reporting on similar predictive factors. Summary odds ratio (OR) or mean difference (MD) is reported with 95% CI. Heterogeneity was assessed using the I2 statistic. Methodological quality was assessed using the Quality in Prognosis Studies tool.

RESULTS

A total of 2805 records were screened and 21 met the inclusion criteria (16 prospective cohort studies, three retrospective cohort studies and two interventional non-randomized trials). Increasing gestational age at delivery (MD, 0.34 (95% CI, 0.04-0.64) weeks), shorter antepartum perineal body length (MD, -0.60 (95% CI, -1.09 to -0.11) cm), labor augmentation (OR, 1.81 (95% CI, 1.21-2.71)), instrumental delivery (OR, 2.13 (95% CI, 1.13-4.01)), in particular forceps extraction (OR, 3.56 (95% CI, 1.31-9.67)), shoulder dystocia (OR, 12.07 (95% CI, 1.06-137.60)), episiotomy use (OR, 1.85 (95% CI, 1.11-3.06)) and shorter episiotomy length (MD, -0.40 (95% CI, -0.75 to -0.05) cm) were associated with US-OASI. When pooling incidence rates, 26% (95% CI, 20-32%) of women who had a first vaginal delivery had US-OASI (20 studies; I2  = 88%). In studies reporting on both clinical and US-OASI rates, 20% (95% CI, 14-28%) of women had AS trauma on ultrasound that was not reported clinically at childbirth (16 studies; I2  = 90%). No differences were found in maternal age, body mass index, weight, subpubic arch angle, induction of labor, epidural analgesia, episiotomy angle, duration of first/second/active-second stages of labor, vacuum extraction, neonatal birth weight or head circumference between cases with and those without US-OASI. Antenatal perineal massage and use of an intrapartum pelvic floor muscle dilator did not affect the odds of US-OASI. Most (81%) studies were judged to be at high risk of bias in at least one domain and only four (19%) studies had an overall low risk of bias.

CONCLUSION

Given the ultrasound evidence of structural damage to the AS in 26% of women following a first vaginal delivery, clinicians should have a low threshold of suspicion for the condition. This systematic review identified several predictive factors for this. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

Understanding the physiology of human defaecation and disorders of continence and evacuation

The act of defaecation, although a ubiquitous human experience, requires the coordinated actions of the anorectum and colon, pelvic floor musculature, and the enteric, peripheral and central nervous systems. Defaecation is best appreciated through the description of four phases, which are, temporally and physiologically, reasonably discrete. However, given the complexity of this process, it is unsurprising that disorders of defaecation are both common and problematic; almost everyone will experience constipation at some time in their life and many will develop faecal incontinence. A detailed understanding of the normal physiology of defaecation and continence is critical to inform management of disorders of defaecation. During the past decade, there have been major advances in the investigative tools used to assess colonic and anorectal function. This Review details the current understanding of defaecation and continence. This includes an overview of the relevant anatomy and physiology, a description of the four phases of defaecation, and factors influencing defaecation (demographics, stool frequency/consistency, psychobehavioural factors, posture, circadian rhythm, dietary intake and medications). A summary of the known pathophysiology of defaecation disorders including constipation, faecal incontinence and irritable bowel syndrome is also included, as well as considerations for further research in this field.

Obstetric anal sphincter injuries: strategies for prevention, diagnosis, and management

Obstetric anal sphincter injuries (OASIS) are one of the most common causes of anal incontinence (AI) in women of reproductive age and can have a significant impact on quality of life. However, many women do not report symptoms to their physicians because of embarrassment and shame. Therefore, prevention and diagnosis of the tear is essential. Diagnostic strategies have evolved considerably in recent years, with an increase in prevalence of OASIS as a consequence. The use of 3D endoanal (3D-EAUS) and 4D transperineal ultrasound (4D-TPUS), in addition to standard clinical examination have enhanced the detection of OASIS. Once identified, adequate repair by a skilled practitioner and optimal postpartum management should be ensured in order to reduce the risk of anal incontinence. This review presents the available evidence on strategies for prevention, diagnosis, and management of OASIS.

Risk of obstetric anal sphincter injuries (OASIS) and anal incontinence: A meta-analysis

BACKGROUND

Obstetric anal sphincter injuries (OASIS) are the commonest cause of anal incontinence in women of reproductive age. We determined the risk of anal sphincter defects diagnosed by ultrasound, and the risk of anal incontinence in (i) all women who deliver vaginally, (ii) in women without clinical suspicion of OASIS, and (iii) after primary repair of sphincter injury, by systematic review.

METHODS

We searched major databases until June 2018, without language restrictions. Random effects meta-analysis was used to obtain pooled estimates of ultrasound diagnosed OASIS and risk of anal incontinence symptoms at various time points after delivery, and of persistent sphincter defects after primary repair. We reported the association between ultrasound diagnosed OASIS and anal incontinence symptoms using relative risk (RR) with 95 % CI.

RESULTS

We included 103 studies involving 16,110 women. Of all women who delivered vaginally, OASIS were diagnosed on ultrasound in 26 % (95 %CI, 21-30, I² = 91 %), and 19 % experienced anal incontinence (95 %CI, 14-25, I² = 92 %). In women without clinical suspicion of OASIS (n = 3688), sphincter defects were observed in 13 % (10-17, I² = 89 %) and anal incontinence experienced by 14 % (95 % CI: 6-24, I² = 95 %). Following primary repair of OASIS, 55 % (46-63, I² = 98 %) of 7549 women had persistent sphincter defect with 38 % experiencing anal incontinence (33-43, I² = 92 %). There was a significant association between ultrasound diagnosed OASIS and anal incontinence (RR 3.74, 2.17-6.45, I² = 98 %).

INTERPRETATION

Women and clinicians should be aware of the high risk for sphincter defects following vaginal delivery even when clinically unsuspected. This underlines the need of careful and systematic perineal assessment after birth to mitigate the risk of missing OASIS. We also noted a high rate of persistent defects and symptoms following primary repair of OASIS. This dictates the need for provision of robust training for clinicians to achieve proficiency and sustain competency in repairing OASIS.

Relationships between the results of anorectal investigations and symptom severity in patients with faecal incontinence

PURPOSE

Anorectal dysfunction is the focus of diagnostic investigations for faecal incontinence. However, severity of incontinence and anorectal investigation results can be discordant. The aim of this study was to define the relationships between anorectal investigation results and incontinence severity to determine which measures, if any, were predictive of incontinence severity.

METHODS

Patients presenting for investigation of faecal incontinence completed a symptom questionnaire, anorectal manometry, rectal sensation, pudendal nerve terminal motor latency, and endoanal ultrasound. Bivariate analyses were conducted between the Jorge-Wexner score and investigation results. Subgroup analyses were performed for gender and symptom subtypes (urge, passive, mixed). A multiple regression analysis was performed.

RESULTS

Five hundred and thirty-eight patients were included. There were weak correlations between the Jorge-Wexner score and maximal squeeze pressure [r = - 0.24, 95%CI(- 0.31, - 0.16), p < 0.001], and resting pressure [r = - 0.18, (95%CI(- 0.26, - 0.10), p < 0.001]. In men only, there were significant associations between the Jorge-Wexner score and endoanal sonography [IAS defects: t(113) = - 2.26, p = 0.03, d = 0.58, 95%CI(- 4.38, - 0.29)] and rectal sensation (MTV: r_s = - 0.24, 95%CI(- 0.41, - 0.06), p = 0.01). No substantial differences were observed in the urge/passive/mixed subgroup analyses. Multiple regression analysis included three variables: age (β = 0.02, p = 0.17), maximal resting pressure (β = - 0.01, p = 0.28), and maximal squeeze pressure (β = - 0.01, p < 0.01). The variance in the Jorge-Wexner score accounted for by this model was < 10%, (R² = 0.07, p = < 0.01, adjusted R² = 0.06).

CONCLUSION

Anorectal investigations cannot predict the severity of faecal incontinence. This may be due to limitations of diagnostic modalities, the heterogeneity of anorectal dysfunction in these patients, or contributing factors which are extrinsic to the anorectum.

Pubovisceral muscle and anal sphincter defects in women with fecal or urinary incontinence after vaginal delivery

BACKGROUND

Vaginal delivery is the most frequent cause of direct anal sphincter trauma as well as pelvic floor muscle defects in women with corresponding signs and symptoms. The aim of the present study was to identify anatomical and functional abnormalities of the anal canal and pelvic floor in women who had had a vaginal delivery and determine the relationship between such abnormalities and the symptoms and severity of fecal incontinence (FI).

METHODS

Consecutive female patients with symptoms of fecal and/or urinary incontinence were recruited through the colorectal and gynecological outpatient clinics at two large university hospitals and were eligible if they had had at a vaginal delivery. All women were assessed for symptoms FI by means of the Cleveland Clinic Florida Incontinence Scale (CCFIS) and for urinary incontinence symptoms, including the presence of complaints of any involuntary leakage of urine, leakage on exertion, sneezing, or coughing, and/or leaking or losing urine associated with an urge to urinate. All women underwent anorectal and endovaginal three-dimensional ultrasonography and anal manometry. The extent of the anal sphincter and PVM defects identified by ultrasound was scored from 1 to 6 based on the longitudinal involvement of the external and internal anal sphincter, the radial angle of the anterior external anal sphincter defect and the longitudinal involvement of the PVM.

RESULTS

There were 130 women and 89 (68%) had at least one defect of the anal sphincter or the pubovisceral muscle or both (42/32% had a pubovisceral muscle defect with or without sphincter defects, 47/36% women had an intact pubovisceral muscle but sphincter defect); and 41 (32%) had intact anal sphincter and pubovisceral muscles. The mean levator hiatus area at rest in women with anal sphincter and/or pubovisceral muscle defects was 18 (± 4 SD) which was significantly greater than in women with no defects (16 ± 3 SD; p = 0.01). Women with PVM defects had significantly higher ultrasound scores (median ultrasound score = 4/range 1-10 vs Intact = 2/range 2-5), indicating more extensive defects (p = 0.001). Bivariate analysis revealed a positive association (p < 0.05) between increasing FI symptom severity (CCFIS score) and women with PVM defects (ρ = 0.6913). Within the group of women with defects mean maximum anal squeeze pressure was significantly lower in women with PVM defect (mean 73 ± 34 SD mmHg vs mean 93 ± 38 SD; p = 0.04). Women with PVM defects had significantly higher median CCFIS scores (median score, 7/range 0-16) compared to women with intact PVM (4/range 0-10) (p < 0.001). There was a significant positive correlation between the CCFIS and ultrasound scores (ρ = 0.625; p < 0.001). Bivariate analysis revealed a negative correlations between the CCFIS score and the lengths of the anterior EAS (ρ = - 0.5621, p < 0.001), IAS (ρ = - 0.40, p < 0.001) and the area of the levator hiatus (ρ = 0.5211, p = 0.001). However, no significant correlations were observed between CCFIS scores and the gap measurement (ρ = 0.101; p = 0.253) or the resting (ρ = - 0.08, p = 0.54) or squeeze pressure (ρ = - 0.12; p = 0.34) values on anal manometry. The variables associated with worsening FI symptom severity (CCFIS score) that remained significant in multiple linear regression included the shorter lengths of the anterior EAS and/or the lengths of the anterior IAS and increased area of the levator hiatus.

CONCLUSIONS

The study data demonstrate that half of the women had combined defects of PVM and sphincter. There were correlations between anatomical abnormalities including the anal sphincter and/or pubovisceral muscle defects with decrease in the anal pressures and increased severity of FI.

Use of 2D and multislice transperineal ultrasonography to describe the degree of perineal laceration following vaginal delivery

Background: Perineal tear is the most common complication after vaginal delivery. Pill-rolling test is a widely used clinical evaluation method to determine the degree of perineal tear. However, the evaluation results of anal sphincter complex (ASC) differ between clinical examination and 2D/multislice transperineal ultrasonography (TPUS). This study aims to describe measurement variation between these modalities.Methods: This cross-sectional study was conducted at Cipto Mangunkusumo Hospital from November 2015 to May 2016. Subjects were primiparous women after vaginal delivery. Clinical examination using pill-rolling test was performed to determine the degree of perineal laceration. Suture was conducted accordingly. The subjects were subjected to 2D/multislice TPUS 72 hours after delivery to evaluate the integrity of internal and external anal sphincters. Data were collected and analyzed to determine compatibility between these examinations.Results: Among 70 prospective primiparous women, five were excluded due to unavailability to undergo 2D/multislice TPUS 72 hours after delivery. The mean duration to perform 2D/multislice TPUS was 4.5 minutes, and pain was tolerable during the examination. The compatibility values of clinical examination with 2D and multislice TPUS were 0.98 and 0.93, respectively, with Cohen’s kappa of 0.92 (95% CI 0.81–1.00) and 0.79 (95% CI 0.58–0.99), respectively.Conclusion: Clinical examination is compatible with 2D/multislice TPUS for determining the degree of perineal tear after vaginal delivery.

The evaluation of the effect of vaginal delivery and aging on anal sphincter anatomy and function

OBJECTIVE

This study was conducted to evaluate the effect of vaginal delivery and aging on anal sphincter anatomy and function.

METHOD

Asymptomatic thirty women were included in this prospective study. Group 1 included 10 women (age range: 18-50) who had never been pregnant. Group 2 included 10 women (age range: 18-50) who had vaginal delivery. Group 3 included 10 women over 50 who had vaginal delivery.

RESULTS

There was no statistically significant difference between the three groups in terms of resting and squeeze pressures. It was found that sphincter thickness showed statistically significant difference between the group 1 and group 3, and also group 2 and group 3. There was not statistically significant difference between the group 1 and group 2 in terms of sphincter thickness. There was a positive correlation between the age and sphincter thickness in all groups. In terms of sphincter thickness and pressure findings there was a positive correlation between the squeeze pressure and external anal sphincter thickness only in group 3.

CONCLUSION

The vaginal delivery did not have a negative influence on the structure and function of the anal sphincter in asymptomatic women. However, it was found that anal sphincter thickness changed strongly in a positive manner with aging.

Postpartum two- and three-dimensional ultrasound evaluation of anal sphincter complex in women with obstetric anal sphincter injury

OBJECTIVE

To compare the sensitivity and specificity of two- (2D) and three- (3D) dimensional transperineal ultrasound (TPUS) and 3D endovaginal ultrasound (EVUS) with the gold standard 3D endoanal ultrasound (EAUS) in detecting residual defects after primary repair of obstetric anal sphincter injuries (OASIS).

METHODS

External (EAS) and internal (IAS) anal sphincters were evaluated by the four ultrasound modalities in women with repaired OASIS. 2D-TPUS was evaluated in real-time, whereas 3D-TPUS, 3D-EVUS and 3D-EAUS volumes were evaluated offline by six blinded readers. The presence/absence of any tear in EAS or IAS was recorded and defects were scored according to the Starck system. Sensitivity, specificity and predictive values were calculated, using 3D-EAUS as reference standard. Inter- and intraobserver analyses were performed for all 3D imaging modalities. Association between patients' symptoms (Wexner score) and ultrasound findings (Starck score) was calculated.

RESULTS

Images from 55 patients were analyzed. Compared with findings on 3D-EAUS, the agreement for EAS evaluation was poor for 3D-EVUS (κ = 0.01), fair for 2D-TPUS (κ = 0.30) and good for 3D-TPUS (κ = 0.73). The agreement for IAS evaluation was moderate for both 3D-EVUS (κ = 0.41) and 2D-TPUS (κ = 0.52) and good for 3D-TPUS (κ = 0.66). Good intraobserver (3D-EAUS, κ = 0.73; 3D-TPUS, κ = 0.78) and interobserver (3D-EAUS, κ = 0.68; 3D-TPUS, κ = 0.60) agreement was reported. Significant association between Starck and Wexner scores was found only for 3D-EAUS (Spearman's rho = 0.277, P = 0.04).

CONCLUSIONS

2D-TPUS and 3D-EVUS are not accurate modalities for the assessment of anal sphincters after repair of OASIS. 3D-TPUS shows good agreement with the gold standard 3D-EAUS and a high sensitivity in detecting residual defects. It, thus, has potential as a screening tool after primary repair of OASIS. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Management of fourth degree obstetric perineal tear without colostomy using non - stimulated gracilis - our experience over eleven years

Background:

Although gracilis muscle transposition for faecal incontinence has been well-described method, its literature for use in obstetric perineal tear without colostomy is sparse. In this study, we have tried to analyse its use in fourth-degree obstetric perineal tears.

Patients and Methods:

A total of 30 patients with recto-vaginal fistula with faecal incontinence secondary to obstetric perineal tear were retrospectively studied between February 2003 and May 2014. The recto-vaginal fistula was explored, dissected and identification of sphincters was done using muscle stimulator. Fistula closure was done followed by sphincter repair, vaginal tightening procedure and single gracilis transposition. None of the patients had covering colostomy. Faecal incontinence was assessed pre- and post-operatively by digital rectal examination (single examiner), Park's score and Corman's score in all cases and using barium hold and transperineal ultrasonography, manometric studies in a few cases. The outcome was measured at an average follow-up of 8.8 months (7–24 months).

Results:

As per Park's score 26 patients had Grade I continence, two had Grade II and two patients had Grade III continence. Corman's score improved from fair to excellent in 26 patients. The patients in whom manometry was performed showed a remarkable rise in both resting and squeeze pressures. Two patients developed post-operative infections in upper 1/3 thigh incision site and three patients at gluteal region scar site.

Conclusion:

Satisfactory continence following gracilis muscle could be achieved.

Impact of fecal incontinence and its treatment on quality of life in women

Fecal incontinence (FI) is a physically and psychosocially debilitating disorder which negatively impacts quality of life (QOL). It bears a significant burden not only on patients but also on their families, caretakers as well as society as a whole. Even though it is considered a somewhat common condition, especially as women age, the prevalence is often underestimated due to patients' reluctance to report symptoms or seek care. The evaluation and treatment of FI can be also hindered by lack of understanding of the current management options among healthcare providers and how they impact on QOL. This article provides a comprehensive review on the impact of FI and its treatment on QOL in women.

Obstetrics anal sphincter injury and repair technique: a review

The Urogynecology Committee of the Asia and Oceania Federation of Obstetrics and Gynaecology (AOFOG) has held seminars and workshops on various urogynecological problems in each country in the Asia-Oceania area in order to encourage young obstetricians and gynecologists. In 2013, we organized the operative seminar for obstetrical anal sphincter injuries (OASIS) in which we prepared porcine models to educate young physicians in a hands-on workshop at the 23rd Asian and Oceanic Congress of Obstetrics and Gynaecology in Bangkok, Thailand. Laceration of the anal sphincter mostly occurs during vaginal delivery and it can develop into anal sphincter deficiency, which causes fecal incontinence, if an appropriate suture is not performed. OASIS has become an important issue, especially in developing countries. The prevalence of OASIS of more than the third degree is around 5% in primary parous women and the frequency is higher when detected by ultrasonographic evaluation. Several risk factors, such as macrosomia, instrumental labor, perineal episiotomy and high maternal age, have been recognized. In a society where pregnant women are getting older, OASIS is becoming a more serious issue. An intrapartum primary appropriate stitch is important, but the 1-year outcome of a delayed operation after 2 weeks postpartum is similar. A randomized controlled study showed that overlapping suture of the external sphincter is better than that of end-to-end surgical repair. The Urogynecology Committee of the AOFOG would like to continue with educative programs about the appropriate therapy for OASIS.

Effect of vaginal delivery and ageing on the anatomy of the female anal canal assessed by three-dimensional anorectal ultrasound

AIM

The effect of vaginal delivery and ageing on the anatomy of the anal canal was assessed using three-dimensional anorectal ultrasound to determine the interobserver reliability.

METHOD

One-hundred and eighteen asymptomatic women without sphincter damage were grouped according to parity and mode of delivery. They were then stratified by age (≤50 years vs >50 years). Group I consisted of 35 nulliparous women, of mean ages 36 years (n = 20) and 62 years (n = 15), Group II consisted of multiparous women, having one or more vaginal deliveries (n = 43), of mean ages 43 years (n = 20) and 60 years (n = 23) and Group III consisted of women who had a Caesarean section (n = 40) of mean ages 41 years (n = 20) and 56 years (n = 20). The groups were compared with regard to the length and the thickness of the external anal sphincter, the internal anal sphincter, the posterior external sphincter and the puborectalis in all quadrants and the anterior gap. Interobserver variability was assessed.

RESULTS

In women having vaginal delivery the length of the anterior external sphincter was shorter (P = 0.0004) and the gap was longer (P = 0.0306). The external sphincter tended to be thinner in individuals having vaginal delivery (P = 0.0677) and in those subjects over 50 years of age having had a vaginal delivery (P = 0.0164). In nulliparous women, the internal sphincter was thicker in subjects over 50 years of age (P = 0.0229). The intraclass correlation coefficient was 0.755-0.916 for sphincter muscle and gap length and 0.446-0.769 for muscle thickness.

CONCLUSION

Vaginal delivery was associated with a shorter anterior external sphincter, a longer gap and a thinner anterior external sphincter in asymptomatic women. Age was correlated with sphincter thickness, and nulliparous women >50 years of age had a thicker internal sphincter. Three-dimensional ultrasound was found to be a reliable method for measuring anal structures.

Anal physiology testing in fecal incontinence: is it of any value?

INTRODUCTION

The prognostic value of postoperative manometry in fecal incontinence is still controversial. The aims of this study were to establish if Fecal Incontinence Severity Index (FISI) and Fecal Incontinence Quality of Life Scale (FIQL) scores correlate with anal manometry and endoanal ultrasound findings and to define if there is any prognostic value in performing anal manometry after patients are surgically treated for fecal incontinence.

METHODS

Fifty-three patients, all women, were identified. All patients underwent a surgical procedure and were analyzed pre- and postoperatively. Fecal incontinence was assessed using the FISI and FIQL. Patients who did not have these score were excluded. Manometry and ultrasound findings before treatment and manometry findings after treatment were compared with surgical patient's incontinence scores. Anal canal length was noted, and its association with the pre- and postoperative manometry finding and incontinence scores were compared.

RESULTS

No correlation of pre- and postoperative resting and squeeze pressures with incontinence scores was found. Ultrasound findings had no correlation with manometry results and incontinence scores. Anal canal length correlated with both pre- and postoperative manometry findings but not with incontinence scores.

CONCLUSION

Preoperative anal manometry and endoanal ultrasound help in guiding treatment options in patients with fecal incontinence. A decrease in FISI and increase in FIQL scores after a sphincter repair quantifies improvement after incontinence surgery, while changes in anal manometry pressures readings do not.

Surgery and sacral nerve stimulation for constipation and fecal incontinence

Fecal continence is a complex bodily function, which requires the interplay of sensation, rectal capacity, and anal neuromuscular function. Fecal incontinence affects approximately 2% of the population and has a prevalence of 15% in elderly patients. Constipation is one of the most common gastrointestinal disorders. The variety of symptoms and risk factors suggest a multifactorial origin. Before any invasive intervention, the surgeon should have a thorough understanding of the etiology of these conditions. Appropriate medical management can improve symptoms in the majority of patients. Surgery is indicated when all medical possibilities are exhausted. This review discusses the most used surgical procedures emphasizing the latest experiences. Sacral nerve stimulation (SNS) is a promising option for patients with fecal incontinence and constipation. The procedure affords patients improved continence and quality of life. The mechanism of action is still poorly understood. This treatment has been used before in other more invasive surgical procedures or even after their failure to improve patients' symptoms and avoid a definitive stoma. Before any invasive intervention, the surgeon should have a thorough understanding of the etiology of these conditions. Appropriate medical management can improve symptoms in the majority of patients. Surgery is indicated when all medical possibilities are exhausted. This review discusses the most used surgical procedures emphasizing the latest experiences. Sacral nerve stimulation (SNS) is a promising option for patients with fecal incontinence and constipation. The procedure affords patients improved continence and quality of life. The mechanism of action is still poorly understood. This treatment has been used before in other more invasive surgical procedures or even after their failure to improve patients' symptoms and avoid a definitive stoma.

Anal resting pressures at manometry correlate with the Fecal Incontinence Severity Index and with presence of sphincter defects on ultrasound

INTRODUCTION

We describe the relationship between anorectal manometry, fecal incontinence severity, and findings at endoanal ultrasound.

METHODS

A total of 351 women completed the Fecal Incontinence Severity Index, underwent anorectal manometry, and endoanal ultrasound. Severity index and manometry pressures in 203 women with intact sphincters on ultrasound were compared with pressures in 148 women with sphincter defects. Relationships between resting and squeeze pressures, severity index, and size of sphincter defects were evaluated.

RESULTS

Mean severity index in patients with and without sphincter defect was 35.7 vs. 36.7 (not significant). Worsening index correlated with worsening mean and maximum resting pressure (P < 0.0001). Differences were observed in mean and maximum resting pressure between the patients with and without sphincter defects (26.6 vs. 37.2, P < 0.0001; 39.4 vs. 51.7, P < 0.001). Resting pressures correlated with the sizes of defect (P < 0.0001).

CONCLUSIONS

Patients with and without sphincter defects had similar severity scores, but patients with defects had a significant decrease in resting pressures. Patients with larger sphincter defects had lower severity scores and resting pressures. Until a manometry cutoff can be set to discriminate between absence and presence of defects, both manometry and ultrasound should be offered to patients with history of anal trauma.

Obstetric anal sphincter injury: incidence, risk factors, and management

BACKGROUND AND AIMS

Obstetric sphincter damage is the most common cause of fecal incontinence in women. This review aimed to survey the literature, and reach a consensus, on its incidence, risk factors, and management.

METHOD

This systematic review identified relevant studies from the following sources: Medline, Cochrane database, cross referencing from identified articles, conference abstracts and proceedings, and guidelines published by the National Institute of Clinical Excellence (United Kingdom), Royal College of Obstetricians and Gynaecologists (United Kingdom), and American College of Obstetricians and Gynecologists.

RESULTS

A total of 451 articles and abstracts were reviewed. There was a wide variation in the reported incidence of anal sphincter muscle injury from childbirth, with the true incidence likely to be approximately 11% of postpartum women. Risk factors for injury included instrumental delivery, prolonged second stage of labor, birth weight greater than 4 kg, fetal occipitoposterior presentation, and episiotomy. First vaginal delivery, induction of labor, epidural anesthesia, early pushing, and active restraint of the fetal head during delivery may be associated with an increased risk of sphincter trauma. The majority of sphincter tears can be identified clinically by a suitably trained clinician. In those with recognized tears at the time of delivery repair should be performed using long-term absorbable sutures. Patients presenting later with fecal incontinence may be managed successfully using antidiarrheal drugs and biofeedback. In those who fail conservative treatment, and who have a substantial sphincter disruption, elective repair may be attempted. The results of primary and elective repair may deteriorate with time. Sacral nerve stimulation may be an appropriate alternative treatment modality.

CONCLUSIONS

Obstetric anal sphincter damage, and related fecal incontinence, are common. Risk factors for such trauma are well recognized, and should allow for reduction of injury by proactive management. Improved classification, recognition, and follow-up of at-risk patients should facilitate improved outcome. Further studies are required to determine optimal long-term management.

Biofeedback vs. electrostimulation in the treatment of postdelivery anal incontinence: a randomized, clinical trial

PURPOSE

This study was designed to evaluate the effect of biofeedback and electrostimulation in a randomized, clinical trial for the treatment of patients with postdelivery anal incontinence.

METHODS

Forty-nine females who sustained third-degree or fourth-degree perineal rupture with a mean age of 36 (range, 22-44) years were included in the study. The females were randomized to biofeedback or electrostimulation treatment. Forty females completed the study: 19 in the biofeedback and 21 in the electrostimulation group. Biofeedback or electrostimulation sessions were performed two times daily for eight weeks in each group. Wexner incontinence score, fecal incontinence quality of life scores, and reduced quality of life on visual analog scale were registered before and after treatment. Patients' self-rating of treatment effect also was registered in both groups. The primary outcome measure was the Wexner incontinence score.

RESULTS

There were no differences in treatment effect between groups. Comparing pretreatment status to posttreatment in each group showed no improvement in Wexner score, reduced quality of life, or any of the fecal incontinence quality of life scores. Patients' self-rating of the treatment effect, however, showed a subjective improvement of symptoms both in the biofeedback and in the electrostimulation group (median, 7 vs. 5.)

CONCLUSIONS

This study shows that there was no difference in effect between biofeedback and electrostimulation. Neither biofeedback nor electrostimulation treatments improved Wexner incontinence score, reduced quality of life, or fecal incontinence quality of life scores. Both treatments resulted in improvement of patients' subjective perception of incontinence control.

The prevalence of occult obstetric anal sphincter injury following childbirth--literature review

OBJECTIVE

To calculate the published prevalence of ultrasound-detected occult anal sphincter damage associated with different modes of delivery.

METHODS

A search of the English language literature for articles using keywords describing the prevalence of ultrasound-diagnosed anal sphincter injury following childbirth. The weighted mean prevalence of occult anal sphincter injury was calculated in the following groups: (1) primiparous women (unselected); (2) primiparous women after an unassisted normal vaginal delivery; (3) multiparous women (unselected); (4) following forceps delivery; (5) following ventouse delivery; (6) following cesarean section.

RESULTS

Nineteen articles described ultrasound-diagnosed occult anal sphincter injury. The prevalence in unselected primiparous women (excluding cesarean section) was 29.2% (288/983). After unassisted vaginal delivery in primiparae the prevalence was 21.7% (74/341). The incidence in multiparous women (unselected) is 32.3% (107/331); following forceps delivery 49.1% (131/267) and with ventouse delivery it is 45.2% (66/146). Only one woman (in 173 cases) had anal sphincter injury following cesarean section.

CONCLUSIONS

After a review of the literature, occult anal sphincter injury is mostly associated with the first vaginal delivery and is particularly high following instrumental deliveries. Ventouse is less traumatic than forceps. Cesarean section is protective to the anal sphincter.

Impact of pregnancy and parturition on the anal sphincters and pelvic floor

Incontinence and defecatory difficulties are commonly reported among women and are often ascribed to traumas sustained during childbirth. Specifically, injuries to the anal sphincters (tears) and conformational changes in the various structures that comprise the pelvic floor (prolapse and perineal descent) have been considered as important contributors to the development of anal incontinence, or difficult defaecation (straining, incomplete evacuation), in later life. An understanding of both the effects of pregnancy and parturition on these structures and the natural history of any traumas sustained are, therefore, of key importance. Unfortunately, the literature on these issues, though vast, is far from complete. While it is evident that pregnancy, per se, imposes changes, primarily through hormonal influences, on colonic, ano-rectal and pelvic floor physiology, the long-term impact of such effects is far from clear. Risk factors for the occurrence of significant, though often occult, anal sphincter injuries during birth have been identified and the role of these tears in the etiology of post-partum incontinence has been well delineated. In contrast, the contribution of such intra-partum events to the later onset of incontinence is far from clear and may well have been over-estimated.

Factors associated with postpartum urinary/anal incontinence in primiparous women in Quebec

OBJECTIVE

To identify the factors associated with urinary incontinence (UI), anal incontinence (AI), and combined UI and AI (UI/AI) in primiparous women in Quebec at six months postpartum.

METHODS

A questionnaire was mailed to 2492 primiparous women at six months postpartum to collect data on incontinence status, sociodemographic characteristics, elimination habits, lifestyle, and severity index scales. Obstetric characteristics were obtained via Quebec's Med-Echo databank. Pearson chi-square, t test, analysis of variance, univariate regression, and stepwise modelling techniques were used for data analysis.

RESULTS

The prevalence of UI in responders was 29.6%, of AI, 20.6%, and of combined UI/AI, 10.4%. Significant adjusted odds ratios were (1) for UI, English spoken (2.04 [95% confidence intervals 1.13-3.69]) and shoulder dystocia (2.90 [1.09-7.69]); (2) for AI, age > 35 years (2.13 [1.12-4.03]), duration of second stage of labour (1.67 [1.11-2.51]), and third or fourth degree tears (4.00 [2.32-6.89]); and (3) for UI and AI, age (2.00 [1.04-3.83]), English spoken (2.55 [1.25-5.19]), shoulder dystocia (4.91 [1.76-13.71]), instrumental delivery (2.28 [1.30-3.99]), third or fourth degree tears (3.58 [1.95-6.57]), and episiotomy (2.24 [1.162-4.33]). Caesarean section was associated with less UI (0.45 [0.28-0.72]), and smoking was associated with less AI (0.38 [0.19-0.76]).

CONCLUSION

Combined UI/AI is associated with several obstetrical factors. The association of UI and AI is observed more frequently after complicated delivery (requiring the application of forceps) or involving perineal damage and episiotomy. As most of the identified factors are modifiable, a preventive treatment policy is advisable.

Effect of vaginal delivery on endosonographic anal sphincter morphology

OBJECTIVE

To describe the effect of vaginal delivery with no clinically recognized sphincter tear on endosonographic anal sphincter morphology and sphincter pressure and to relate endosonographic results to anal sphincter pressure and anal incontinence score.

STUDY DESIGN

Thirty-two nullipara underwent anal endosonography and anal manometry in the third trimester of pregnancy, 2 weeks and 6 months post-partum. The sphincter defect scores (1-16) and the thickness and length of the sphincters were measured by endosonography, and sphincter pressures and manometric sphincter lengths were determined. The Wexner incontinence score (1-20) was used to classify anal incontinence 6 months post-partum.

RESULTS

Five (16%) women had small endosonographic anal sphincter defects (score 3-4) before delivery. Eight women (25%; confidence interval 11-43%) had new defects detected post-partum, five small, one moderate (score 7), and two large (score 10-11). Six (75%) of eight women with new defects post-partum had undergone episiotomy versus five (21%) of 24 women with no new defects (p = 0.02). Six months after delivery 16 (50%) women reported anal incontinence, and there was a positive correlation between the endosonographic defect score 6 months post-partum and the Wexner incontinence score. The sphincter was significantly longer during pregnancy than 6 months post-partum.

CONCLUSION

New sphincter defects may arise after vaginal delivery without any clinically recognizable sphincter tear. There is a positive correlation between the endosonographic defect score 6 months post-partum and the Wexner incontinence score.

Obstetric-induced incontinence: A black hole of preventable morbidity

There is a detailed literature comprising clinical and anorectal physiological studies linking faecal incontinence to vaginal delivery. Specific risk factors are high infant birthweight, forceps delivery and prolonged second stage of labour. The onset of symptoms may be delayed for many years. Faecal incontinence occurs in more than 10% of adult females and urinary incontinence in about a third of multiparous women. This places a very large economic burden on the Australian health system. A conservative estimate for overall management of incontinence would be in excess of $A700 million but the actual amount is unknown. Preventative measures for avoiding pelvic floor injuries need to be established, and safe obstetric practice needs to be redefined in the light of current knowledge about incontinence. Outcome measures for safe birthing should not only include infant and maternal mortality and infant morbidity, but should also include the long-term effects of vaginal delivery on the pelvic floor, particularly urinary and faecal incontinence. Several state reports and one federal senate report on safe birthing have been lacking in this area. The safety of birthing centres and home birthing needs to be examined to provide birthing mothers with complete and appropriate information about safety in order that they may consider their options. Appropriate Caesarean section rates for optimal birthing safety are unknown and need to be re-examined. Calls for overall reduction in Caesarean section rates in Australia are inappropriate and cannot be justified until the effects of pelvic floor injury are added to the overall assessment.

Occult anal sphincter injuries--myth or reality?

OBJECTIVES

To establish the true prevalence of clinically recognisable and occult obstetric anal sphincter injuries (OASIS).

DESIGN

Prospective interventional study.

SETTING

Busy district general hospital.

SAMPLE

Two hundred and fifty-four women having their first vaginal delivery over a 12-month period were invited. Two hundred and forty-one (95%) participated and 208 (86%) attended follow up.

METHODS

Women had a clinical examination at delivery by the accoucheur and repeated by an experienced research fellow immediately after delivery. All identified OASIS were verified and repaired by the duty specialist registrar or consultant. Endoanal ultrasound was performed immediately postpartum prior to suturing and repeated seven weeks later.

MAIN OUTCOME MEASURES

Prevalence of recognised and occult anal sphincter injuries.

RESULTS

Fifty-nine (24.5%) women sustained OASIS. The prevalence of OASIS increased significantly from 11% to 24.5% when women were re-examined. Of these, 30 occurred in deliveries by midwives who missed 26 (87%) and 29 following deliveries by doctors who missed 8 (28%) injuries. All clinically apparent OASIS were also identified on endoanal ultrasound. In addition, three (1.2%) women had an occult anal sphincter injury. Two of these occult sphincter injuries were isolated to the internal anal sphincter (IAS) and would not usually be clinically detectable.

CONCLUSIONS

OASIS occur more frequently than previously reported. Many remain undiagnosed and are subsequently classified as occult when identified on anal endosonography. Genuine occult injuries are rare. Training in perineal anatomy and recognition of OASIS needs to be enhanced in order to increase detection of OASIS and minimise the risk of consequent anal incontinence.

The extent of endosonographic anal sphincter defects after primary repair of obstetric sphincter tears increases over time and is related to anal incontinence

OBJECTIVE

To describe and classify endosonographic obstetric sphincter defects at 1 week, 3 months and 1 year after primary repair, and to relate the endosonographic results to anal sphincter pressure and to symptoms of anal incontinence over time.

METHODS

Forty-one women who had suffered a third- or fourth-degree perineal tear at delivery underwent anal endosonography and anal manometry 1 week, 3 months and 1 year after primary suture of the tear. The extent of the endosonographic defects was described using defect scores ranging from 0 (no defect) to 16 (maximal defect), the score taking into account the location and the longitudinal and circumferential extent of the defect. The women answered a questionnaire with regard to bowel function 1 and 4 years after delivery, the degree of incontinence being expressed as a Wexner score.

RESULTS

Some 90% (37/41) of the women had endosonographic defects at 1 week, 3 months and 1 year. The endosonographic defect scores increased significantly between the first and second examinations and then remained unchanged. At 1 year there was a negative correlation between endosonographic sphincter defect score and sphincter pressure. At 1 and 4 years, 54% (22/41) and 61% (25/41) of the women, respectively, had a Wexner score >/= 1. There was a positive correlation between the endosonographic sphincter defect score at 1 week, 3 months and 1 year and the Wexner incontinence score at 1 and 4 years. The endosonographic sphincter defect score at 1 week was the variable that was most predictive of the Wexner score at 4 years (r = 0.48, P = 0.002).

CONCLUSION

The higher the endosonographic sphincter defect score after primary repair of an obstetric sphincter tear the lower the sphincter pressure and the higher the risk of anal incontinence.

Faecal incontinence and mode of first and subsequent delivery: a six-year longitudinal study

OBJECTIVE

To investigate the prevalence of persistent and long term postpartum faecal incontinence and associations with mode of first and subsequent deliveries.

DESIGN

Longitudinal study.

SETTING

Maternity units in Aberdeen, Birmingham and Dunedin.

POPULATION

Four thousand two hundred and fourteen women who returned postal questionnaires three months and six years postpartum.

METHODS

Symptom data were obtained from both questionnaires and obstetric data from case-notes for the index birth and the second questionnaire for subsequent births. Logistic regression investigated the independent effects of mode of first delivery and delivery history.

MAIN OUTCOME MEASURES

Incontinence to bowel motions three months and six years after index birth. For delivery history, the outcome was incontinence only at six years.

RESULTS

The prevalence of persistent faecal incontinence was 3.6%. Almost 90% of these women reported no symptoms before their first birth. The forceps delivery of a first baby was independently predictive of persistent symptoms (OR 2.06, 95% CI 1.40-3.04). A caesarean section first birth was not significantly associated with persistent symptoms (OR 1.07, 95% CI 0.64-1.81). Delivering exclusively by caesarean section also showed no association with subsequent symptoms (OR 1.04, 95% CI 0.72-1.50) but ever having forceps was significantly predictive (OR 1.48, 95% CI 1.18-1.87). Other factors independently associated with persistent faecal incontinence were older maternal age, increasing number of births and Asian ethnic group. Birthweight and long second stage were not significantly associated.

CONCLUSIONS

The risk of persistent faecal incontinence is significantly higher after a first delivery by forceps. We found no evidence of a lower risk of subsequent faecal incontinence for exclusive caesarean section deliveries.

Postpartum Urinary and Anal Incontinence: A Population-Based Study of Quality of Life of Primiparous Women in Quebec

OBJECTIVE

To describe the quality of life of primiparous women with urinary or anal incontinence.

METHODS

A questionnaire was mailed at six months postpartum to 2492 primiparous women living in Quebec. The prevalence of urinary incontinence was assessed at six months postpartum through the FPSUND severity score index; the prevalence of anal incontinence was assessed by the grading system of Vaizey et al.; the quality of life of women who developed incontinence was assessed using the Shumaker's I-QOL for urinary incontinence and Lowry's quality of life instrument for anal incontinence. Descriptive analysis, t-test, analysis of variance, and linear regression were used.

RESULTS

The prevalence of urinary incontinence was 29.6% and of anal incontinence was 20.6%. Quality of life was affected significantly by the presence of urinary incontinence or both forms of incontinence (P 0.001) and by the type of urinary incontinence (P < 0.001). Women with all types of anal incontinence had significantly lower quality of life scores for access to toilet (P < 0.001), lifestyle (P < 0.01), self-esteem (P = 0.037), and total score (P < 0.001). Quality of life correlated with the severity of both urinary incontinence and anal incontinence: the more severe the urinary or anal incontinence, the lower the quality of life score.

CONCLUSION

Women who have urinary or anal incontinence, or both, have significant reductions in indicators of quality of life. Research is needed to evaluate strategies for preventing and treating these problems.

Episiotomy and perineal tears presumed to be imminent: the influence on the urethral pressure profile, analmanometric and other pelvic floor findings--follow-up study of a randomized controlled trial

BACKGROUND

The influence of the restrictive use of episiotomy at perineal tears judged to be imminent on the urethral pressure profile, analmanometric, and other pelvic floor findings is unknown.

METHODS

Follow-up study of a randomized controlled trial with two perineal management policies includes the use of episiotomy: (a) only for fetal indications and (b) in addition at a tear presumed to be imminent. Participants were 146 primiparous women with an uncomplicated singleton pregnancy >34 weeks of gestation. For the intention-to-treat analysis, 68 women after vaginal delivery were included who delivered a live full-term baby between January 1999 and September 2000.

OUTCOME MEASURES

Maximum urethral closure pressure (MUCP, cmH2O), functional urethral length (mm), maximum anal pressure (MAP, mmHg), functional anal sphincter length (ASL, mmHg) at rest and during contraction, and pelvic floor muscle strength (5-grade Oxford score) are the outcome measures. The rate of dyspareunia, urinary incontinence, and anorectal incontinence was documented.

RESULTS

At a mean follow up of 7.3 months, there were no statistically significant differences between the two groups (a versus b): mean MUCP at rest (98 versus 101 cmH2O), during contraction (95 versus 103 cmH2O), mean MAP at rest (113 versus 121 mmHg), during contraction (143 versus 166 mmHg), mean ASL at rest (50 versus 50 mmHg), during contraction (42 versus 45 mmHg), mean pelvic floor muscle strength (2.2 versus 2.6), no pain during sexual intercourse (79 versus 67%), prevalence of urinary incontinence (48 versus 27%), and anorectal incontinence (19 versus 24%).

CONCLUSIONS

Episiotomy at a perineal tear presumed to be imminent does not have any advantage with regard to pelvic floor function and should be avoided.

Endoanal and endorectal ultrasound: applications in colorectal surgery

Endoanal and endorectal ultrasound have an important role in colorectal surgery. They can be applied in the management of faecal incontinence, rectal tumours and inflammatory perianal conditions. In faecal incontinence, anal ultrasound will confirm the presence or absence of sphincter defects. This will direct any operative intervention such as direct sphincter repair. Ultrasound in rectal cancer allows staging of the tumour by assessing the depth of invasion through the bowel wall and involvement of mesenteric nodes. Such staging might influence the choice of operation and determine which patients might benefit from preoperative chemotherapy and radiotherapy. Ultrasound has a particular role in recurrent and complex anal fistula and perianal sepsis. Preoperative and perioperative planning with accurate delineation of fistula tracts, extensions and sphincter involvement might help prevent recurrence and impaired continence from sphincter damage after surgery. Correct interpretation of ultrasound images requires training and experience so that the results can be properly correlated with the clinical situation.

Patient choice cesarean: an evidence-based review

Primary elective cesarean performed on a patient's request now comprises 4% to 18% of all cesareans and 14% to 22% of elective cesareans in reported series. Patients most commonly choose cesarean because of tocophobia, or fear of childbirth. Almost two thirds of obstetricians surveyed are willing to perform cesarean on request, citing decreased risk of pelvic floor or fetal injury, maintenance of sexual functioning, and physician and patient convenience. Contrasting these beliefs are the limited available data on short- and long-term maternal and perinatal morbidity and mortality that generally favor vaginal delivery. Moreover, comprehensive economic impact assessments of cesarean on request are lacking, and professional organizations do not agree on the ethics of offering patient choice cesarean.

TARGET AUDIENCE

Obstetricians & Gynecologists, Family Physicians.

LEARNING OBJECTIVES

After completion of this article, the reader should be able to list the reasons that women and obstetricians choose elective cesarean delivery, to outline the ethical aspects of cesarean delivery, and to describe the material and fetal morbidity and mortality associated with cesarean delivery compared to vaginal delivery.

Anal function following third degree tears

OBJECTIVE

To assess the anal function of women who have suffered a third degree perineal tear during parturition.

PATIENTS

Fifty-three consecutive women who sustained a third degree tear, between January 1998 and March 2000, at the Princess Anne Maternity Unit, Royal Bolton Hospital were assessed.

METHODS

Women were assessed at 3 months post partum using the Cleveland Clinic Incontinence Score, digital assessment of anal sphincter and endo-anal ultrasound scan.

RESULTS

At 3 months post partum 75% of the participants had no symptoms of anal incontinence, 18% had mild symptoms and 7% had more severe symptoms. Anal endosonography demonstrated normal anal sphincters in 66% of participants, an abnormality in the external sphincter in 29% and a defect in both sphincters in 2%. There was poor correlation between symptoms and scan defects.

CONCLUSION

The incidence of anal incontinence following repair of a third degree tear was not high and it is unlikely that we are missing a hidden pool of symptomatic women. No major change in management policy is required. The routine assessment of anal function in women who had sustained a third degree tear was appreciated by the women and enabled us to identify the small portion of women with significant symptoms.

Anal sphincter function and integrity after primary repair of third‐degree tear: uncontrolled prospective analysis

BACKGROUND

The purpose of the present paper was to determine the anatomical integrity and functional effect of a tear to the anal sphincter in women after vaginal delivery.

METHODS

A prospective review of third- and fourth-degree vaginal tears over a 3 year period at Lyell McEwin and Queen Elizabeth Hospitals, Adelaide. Obstetric details were obtained from the records. All were counselled by a continence advisor and offered consultation with a colorectal surgeon. The integrity of the anal sphincter was assessed by endoanal ultrasound.

RESULTS

During the study period there were 6875 vaginal deliveries. There were 89 women (1.3%) who had a third- or fourth-degree tear. Fifty-one (57%) agreed to participate. Primiparity (67%), episiotomy (49%), forceps delivery (29%) and instrumental delivery were common in women sustaining a tear. Symptoms of anal incontinence (mild) or faecal urgency were described in 23 women (45%). Except for three women with an anovaginal fistula none required surgery for the management of faecal incontinence. A sphincter defect was seen in 27 women (53%) on endoanal ultrasound. The presence or absence of a sphincter defect was not significantly associated with symptoms but a trend was suggested (chi2=3.21; P=0.07).

CONCLUSIONS

Third-degree tear after vaginal delivery was a significant intrapartum event, yet associated only with minimal symptoms (excluding patients with anovaginal fistula) even in the presence of a sphincter defect on anal ultrasound.

Anal sphincter injury during vaginal delivery--an argument for cesarean section on request?

AIMS

Fear of damage to the pelvic floor from vaginal delivery and long-term sequelae (urinary and anal incontinence) sometimes being cited as an indication for cesarean section on request. The aim of the present study was to compare the effects of vaginal delivery versus elective cesarean section on anal sphincter function.

MATERIAL AND METHODS

We studied 71 consecutive women six weeks before delivery, 52 of them 4-6 weeks after delivery, and all patients with occult sphincter lesions 3 months after delivery. A bowel function questionnaire was completed, and anal endosonography, manometry, and measurement of the pudendal-nerve terminal motor latency were performed.

RESULTS

Forty-two (80.8 percent) patients were delivered vaginally, ten (19.2 percent) by elective cesarean section at term. Clinically recognized anal sphincter injuries occurred in 9.5 percent (4) of patients, two of them developed incontinence for gas. The overall incidence of anal incontinence after vaginal delivery was 4.8 percent. Occult sphincter defects were identified endosonographically in 19 percent (8) of women, there was no reported case of any anal incontinence 3 months after delivery. No woman delivered by cesarean section had altered anal continence or any significant change in anal pressures, rectal sensibility, and PNTML.

CONCLUSION

Severe sphincter tear is the single most important factor leading to anal incontinence in women, whereas occult sphincter defects are rarely associated with short-term sequelae, but may predispose to the development of anal incontinence later on in life. Elective cesarean section should be recommended for women at increased risk for anal incontinence.

Do occult anal sphincter injuries, vector volume manometry and delivery variables have any predictive value for bowel symptoms after first time vaginal delivery without third and fourth degree rupture? A prospective study

BACKGROUND

The aim of this study was to determine whether there exists a correlation between anal incontinence, occult sphincter injuries, anal manometry values, and delivery variables in primiparous women after first time vaginal delivery.

METHODS

Eighty-six primigravida women were recruited for this study. Transanal ultrasonography (TAUS) and vector volume manometry (VVM) was performed and bowel symptoms were recorded at 25 weeks of pregnancy and 5 months after labor. Incontinent women at 5 months after vaginal delivery were interviewed again at 12 months.

RESULTS

Nineteen women (25%) experienced flatus incontinence postpartum. After 12 months, only one-third of the women were still incontinent. Fourteen women (19%) showed abnormal TAUS of the anal sphincter. Of the delivery variables, only baby head circumference was significantly associated with flatus incontinence (p = 0.01). There was no correlation between flatus incontinence or delivery variables and anal sphincter injuries; VVM values were not associated with either anal sphincter injuries or flatus incontinence at 5 months, but VVM values were negatively associated with flatus incontinence at 12 months after labor.

CONCLUSIONS

At 5 months after labor, flatus incontinence is relatively common, and is not associated with reduced VVM values. Two-thirds of women recover from flatus incontinence during the first year. Women who had flatus incontinence persisting for a minimum of 1 year had reduced VVM values. Anal sphincter injuries as seen by TAUS are not associated with either VVM values or any delivery variable. Baby head circumference is the only delivery variable significantly associated with flatus incontinence.

[Anal incontinence: echographic and manometric study]

STUDY AIM

The goal of this study was to evaluate the clinical and functional consequences of anal sphincter echographic lesions in patients with fecal incontinence.

PATIENTS AND METHOD

From January 1997 to April 2001, 100 patients with fecal incontinence (90 women, 10 men) were prospectively explored by transanal ultrasound and vectormanometry. Internal and external sphincter defects, as well as their extension, were analyzed with regard to their clinical and functional expressions (resting and squeeze anal sphincter pressures, anal sphincter asymmetry index).

RESULTS

Among the 100 patients, 42 had no echographic lesions, 58 had a defect: 26 had an isolated defect (internal sphincter (n = 3), external sphincter (n = 23) and 32 had combined internal and external sphincter defects. Squeeze anal pressures were significantly lower in the group of patients with combined defects, compared to the group with isolated defect or without defect. Anal asymmetry index was higher in the group of patients with combined defects, compared to the other groups. There was a positive correlation between the radial extension of the defect and the importance of clinical complaints.

CONCLUSION

Echographic anal sphincter lesions are frequent in fecal incontinence and are clinically and functionally significant.

Does a second delivery increase the risk of anal incontinence?

OBJECTIVE

To evaluate the prevalence of anal incontinence and anal sphincter defects after a first vaginal delivery and assess the effect of a second delivery.

DESIGN

Prospective cohort study using postal questionnaires assessing incontinence to flatus and stools at three and thirty months postnatally and anal endosonography at three months following delivery.

SETTING

Recruitment was from the antenatal clinic at the University Hospitals of Geneva, Switzerland.

POPULATION

One hundred women with a vaginal delivery of their first child.

MAIN OUTCOME MEASURES

Prevalence of anal incontinence and anal sphincter defects.

RESULTS

Anal incontinence was reported by 16/92 (17%) of women at three months after delivery and by 11/77 (14%) at 30 months. At that time, 5/54 (9%) with no further delivery reported incontinence, compared with 6/ 23 (26%) of those who had had another delivery (RR 2.8, 95% CI 1.0-8.3). Anal sphincter defects were diagnosed by endosonography in 46/87 (53%) women and were associated with reported incontinence at both three months (RR 1.9; 95% CI 1.4-2.6) and 30 months (RR 1.9: 95% CI 1.3-2.8) after delivery. The prevalence of anal incontinence at 30 months was highest (5/13, 39%) among those in whom a sphincter defect was diagnosed by endosonography after their first delivery and with a second delivery.

CONCLUSION

Anal incontinence after childbirth is associated with defects of the anal sphincter diagnosed by endosonography. Subsequent deliveries increase the risk of incontinence, particularly among women with a sphincter defect diagnosed after the first delivery.

Postdelivery anal function in primiparous females: ultrasound and manometric study

PURPOSE

A study was performed to evaluate the early morphologic and functional consequences of vaginal delivery on the anal sphincter in primiparous females.

METHODS

Among a cohort of 197 primiparous females who agreed to participate in a clinical evaluation of fecal incontinence and in a transanal ultrasound examination 12 weeks after delivery, 52 also underwent anal manometry using a radial six-port catheter, of whom 10 were asymptomatic and had a normal sphincter at ultrasound and the remaining 42 had clinical signs of anal incontinence or ultrasonographic defects of the anal sphincter or both. Anal sphincter pressures and asymmetry index were analyzed at rest and during voluntary squeeze. Manometric and ultrasound results were compared, together with clinical symptoms.

RESULTS

Fourteen patients with clinical signs of anal incontinence had lower resting and squeeze anal pressures than continent patients (P < 0.05), but similar anal asymmetry indexes. Patients with incontinence and an anal defect had the lowest resting and squeeze anal pressures (P < 0.05). Forceps assistance to delivery was not associated with a higher frequency of anal sphincter lesions. Resting and squeeze anal pressures were lower in the forceps group (P < 0.005), but anal asymmetry indexes were similar. Finally, manometric results were identical in the presence or absence of anal sphincter endosonographic defects.

CONCLUSIONS

Anal sphincter defects are frequent after the first vaginal delivery, but are not always associated with functional or clinical abnormalities. Resting and squeeze anal pressures were significantly decreased in patients with incontinence and an anal defect and after forceps-assisted deliveries. Anal asymmetry index was not found useful in this population of young primiparous females.

Effect of delivery on anal sphincter morphology and function

PURPOSE

Anal sphincter injury is a serious complication of childbirth, which may result in persistent anal incontinence. Occult injuries, visualized with endoanal ultrasonography, have previously been reported in up to 35 percent of females in a British study. The aim of the present study was to study anal sphincter morphology and function before and after delivery in primiparous females in the United States.

METHODS

Thirty-eight primiparous patients (mean age, 31 years) were evaluated with endoanal ultrasonography, anal manometry, and pudendal nerve terminal motor latency during pregnancy and after delivery. Bowel function before and after delivery was recorded according to set questionnaires. Cesarean section was performed in three patients.

RESULTS

Clinical sphincter tears, requiring primary repair, occurred in 15 percent of the patients. After delivery endoanal ultrasonography revealed disruptions in the external anal sphincter in six patients, but no patient had disruption in the internal anal sphincter. One patient had slight scarring in the external sphincter. Of the seven patients with pathologic findings at endoanal ultrasonography, the left pudendal latency increased after delivery (P < 0.05), and manometric results were reduced. Three of these seven patients had a third-degree or fourth-degree tear during delivery. All investigations were normal in the three patients who underwent cesarean section.

CONCLUSIONS

The present study demonstrates a significant frequency of sphincter injuries (20 percent) after vaginal delivery. Obstetricians should be aware of this risk and explicitly inquire about incontinence symptoms at follow-up after delivery.

The effect of vaginal delivery on anal function

The commonest cause of faecal incontinence is considered to be childbirth. In this review we consider the available data on the prevalence of faecal incontinence in the community and the incidence of incontinence after childbirth. The results and implications of studies on childbirth using anal manometry, neurophysiological tests and anal ultrasound are discussed. The development of symptoms are more likely with a third degree tear and forceps delivery. Reduced resting and squeeze pressures are seen early after vaginal delivery with recovery noted with time. Reduced pressures have been seen in symptomatic and asymptomatic women and there is no correlation of the pressures with the presence or absence of a sphincter defect or evidence of pudendal neuropathy. Anal manometry can not be used as an indication of muscle or nerve injury. Both sphincter defects and evidence of pudendal neuropathy are common after vaginal delivery but these are not necessarily associated with symptoms. It is suggested that such occult sphincter injuries may go on to be symptomatic in later life. The number of these injuries, however, is far greater than the documented prevalence of incontinence in the community, and hence many must remain asymptomatic. Their true clinical significance remains uncertain.