Anal sphincter tears at vaginal delivery: risk factors and clinical outcome of primary repair.

OBJECTIVE: To determine risk factors for obstetric anal sphincter tears and to evaluate symptomatic outcome of primary repair. METHODS: Obstetric-procedure, maternal, and fetal data were registered in 845 consecutive vaginally delivered women. Risk factors for anal sphincter tears were calculated by multiple logistic regression. All 808 Swedish-speaking women who delivered vaginally were included in a questionnaire study regarding anal incontinence in relation to the delivery. Questionnaires were distributed within the first few days postpartum, and at 5 and 9 months postpartum. RESULTS: Six percent of the women had a clinically detected sphincter tear at delivery. Sphincter tears were associated with nulliparity (odds ratio [OR] 9.8, 95% confidence interval [CI] 3.6, 26.2), postmaturity (OR 2.5, 95% CI 1.0, 6.2), fundal pressure (OR 4.6 95% CI 2.3, 7.9), midline episiotomy (OR 5.5 95% CI 1.4,18.7), and fetal weight in intervals of 250 g (OR 1.3 95% CI 1.1, 1.6). Fifty-four percent of women with repaired sphincter tears suffered from fecal or gas incontinence or both at 5 months and 41% at 9 months. Most of the symptoms were infrequent and mild. CONCLUSION: Several risk factors for sphincter tear were identified. Sphincter tear at vaginal delivery is a serious complication, and it is frequently associated with anal incontinence. Special attention should be directed toward risk factors for this complication. Symptoms of anal incontinence should explicitly be sought at follow-up after delivery.     

Endoanal ultrasound findings and fecal incontinence symptoms in women with and without recognized anal sphincter tears

OBJECTIVE: To estimate whether endoanal ultrasound findings are more prevalent in primiparous women with a history of anal sphincter tear than in women without this history and whether the findings are associated with fecal incontinence symptoms. METHODS: A total of 251 primiparous women at seven clinical sites underwent standardized ultrasound assessment of the internal and external anal sphincter 6-12 months after delivery. Participants were women in the three cohorts of the Childbirth and Pelvic Symptoms Study: 1) women with clinically evident third- or fourth-degree tear at vaginal delivery (n=106); 2) no tear at vaginal delivery (n=106); and 3) cesarean delivery without labor (n=39). Women completed the Fecal Incontinence Severity Index to assess fecal incontinence symptoms. RESULTS: Thirty-five percent of the sphincter tear group exhibited internal sphincter gaps compared with 3% of vaginal controls (odds ratio [OR] 18.4, 95% confidence interval [CI] 5.5-62.1) and 10% of cesarean controls. External sphincter gaps were identified in 51% of the tear group compared with 31% of vaginal controls (OR 2.3, 95% CI 1.3-4.0) and 28% of cesarean controls. In the tear group, fecal incontinence severity was greater in those with internal sphincter gaps compared with those with no internal sphincter gaps (Fecal Incontinence Severity Index score 6.6+/-8.3 compared with 3.3+/-6.1, P=.02), as well as in those with external sphincter gaps (6.1+/-8.4 compared with 2.7+/-5.0, P=.01), and greatest in those with both internal and external sphincter gaps compared with at least one gap not present (7.2+/-8.1 compared with 3.4+/-6.4, P=.003). CONCLUSION: Anal sphincter gaps detected by ultrasonography are prevalent in postpartum primiparous women with a history of sphincter tear and are associated with fecal incontinence severity. LEVEL OF EVIDENCE: II-2.     

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.     

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.     

Urinary and anal incontinence after vacuum delivery

OBJECTIVES: To evaluate urinary and fecal incontinence symptoms, and occult anal sphincter defects in women after vacuum and spontaneous vaginal delivery. STUDY DESIGN: In a case-control study, 50 primiparous women delivered by vacuum extraction were compared to 50 women delivered spontaneously. Urinary and anal incontinence symptoms, pelvic floor muscle strength and sphincter defects on endoanal ultrasound were evaluated 6-24 weeks postpartum. RESULTS: New anal incontinence symptoms after childbirth were found in 30% of the vacuum group compared to 34% of the controls, new urinary incontinence symptoms in 28 and 42%, respectively (not significant). After excluding Grade III perineal tear, sonographic sphincter defects were found in 11 (27.5%) after vacuum delivery compared to 4 (10%) after spontaneous delivery (P<0.05, chi(2)-test). CONCLUSION: Anal and urinary incontinence symptoms are frequent after vaginal delivery. Vacuum delivery causes more sonographic sphincter defects but appears to cause no more harm to pelvic floor function than spontaneous vaginal delivery.     

Anal sphincter damage after vaginal delivery: functional outcome and risk factors for fecal incontinence

OBJECTIVE: To assess the role of anal sphincter damage following delivery in the development of anorectal complaints and urinary incontinence, and to identify obstetric factors associated with subsequent fecal incontinence. METHODS: The retrospective cohort study with matched controls used a postal questionnaire and analysis of delivery and operation records from all women who underwent primary repair of a third or fourth degree perineal rupture in our hospital between 1971 and 1991, and their controls, matched for date and parity. Frequencies of complaints were compared using the Mantel-Haenszel common odds ratio [OR] for matched-control studies. Obstetric risk factors for fecal incontinence were assessed with multivariate logistic regression analysis. RESULTS: In the period studied, 171 women underwent a primary repair. One hundred and forty-seven of which returned the questionnaire (86%), compared with 131 of the controls (73%). Analysis was performed on 125 matched pairs with a median follow-up of 14 years. Fecal incontinence was reported by 39 patients and 16 controls (OR: 3.09; 95% confidence interval: 1.57-6.10). Urinary incontinence was reported by 65 cases and 52 controls (OR:1.46; 95% CI: 0.91-2.37). Among women with anal sphincter damage, the extent of anal sphincter damage was an independent risk factor for fecal incontinence. (OR: 2.54; 95% CI: 1.45-4.45). Subsequent vaginal delivery was not associated with the development of fecal incontinence (OR: 2.32; 95% CI: 0.85-6.33). In primiparous women mediolateral episiotomy protected for fecal incontinence after anal sphincter damage (OR: 0.17; 95% CI: 0.05-0.60). CONCLUSIONS: Anal sphincter damage following delivery is significantly associated with subsequent anorectal complaints, but not with urinary incontinence. The extent of sphincter damage is an independent risk factor for the development of fecal incontinence. Mediolateral episiotomy protects for fecal incontinence in primiparous women.     

Diagnosis of anal sphincter tears to prevent fecal incontinence: a randomized controlled trial

OBJECTIVE: Maternal anal sphincter tears after vaginal delivery are frequently not diagnosed clinically and are associated with subsequent fecal incontinence. This study examined whether diagnosis of these tears by ultrasonography, followed by immediate surgical repair, reduces the occurrence of incontinence. METHODS: We conducted a randomized trial involving 752 primiparous women without a clinically evident anal sphincter tear to evaluate the benefit of adding endoanal ultrasonography immediately after vaginal delivery to the standard clinical examination of the perineum. When a sphincter tear was diagnosed, the perineum was surgically explored and the sphincter sutured. The main outcome evaluated was fecal incontinence 3 months postpartum graded by the Wexner incontinence scale, which measures incontinence to flatus and liquid or solid stools, need to wear a pad, and lifestyle alterations. RESULTS: Among women assessed by ultrasonography, 5.6% had a sphincter tear. Severe incontinence was reported 3 months after childbirth by 3.3% of women in the intervention group compared with 8.7% in the control group (risk difference -5.4%; 95% confidence interval -8.9 to -2.0; P = .002). The benefit of the intervention persisted 1 year after delivery, with 3.2% severe incontinence in the intervention group compared with 6.7% in the control group (risk difference -3.5%; 95% confidence interval -6.8% to -0.3%; P = .03). Ultrasonography needs to be performed in 29 women to prevent 1 case of severe fecal incontinence. CONCLUSION: Ultrasound examination of the perineum after childbirth improves the diagnosis of anal sphincter tears, and their immediate repair decreases the risk of severe fecal incontinence. LEVEL OF EVIDENCE: I.     

Fecal and urinary incontinence in primiparous women

OBJECTIVE: To prospectively investigate the relationship between anal sphincter tears and postpartum fecal and urinary incontinence. METHODS: The Childbirth and Pelvic Symptoms study was a prospective cohort study performed by the Pelvic Floor Disorders Network to estimate the prevalence of postpartum fecal and urinary incontinence in primiparous women: 407 with clinically recognized anal sphincter tears during vaginal delivery, 390 without recognized sphincter tears (vaginal controls), and 124 delivered by cesarean before labor. Women were recruited postpartum while hospitalized and interviewed by telephone 6 weeks and 6 months postpartum. We assessed fecal and urinary incontinence symptoms using the Fecal Incontinence Severity Index and the Medical, Epidemiological, and Social Aspects of Aging Questionnaire, respectively. Odds ratios were adjusted for age, race, and clinical site. RESULTS: Compared with the vaginal control group, women in the sphincter tear cohort reported more fecal incontinence (6 weeks, 26.6% versus 11.2%; adjusted odds ratio [AOR] 2.8, 95% confidence interval [CI] 1.8-4.3; 6 months, 17.0% versus 8.2%; AOR 1.9, 95% CI 1.2-3.2), more fecal urgency and flatal incontinence, and greater fecal incontinence severity at both times. Urinary incontinence prevalence did not differ between the sphincter tear and vaginal control groups. Six months postpartum, 22.9% of women delivered by cesarean reported urinary incontinence, whereas 7.6% reported fecal incontinence. CONCLUSION: Women with clinically recognized anal sphincter tears are more than twice as likely to report postpartum fecal incontinence than women without sphincter tears. Cesarean delivery before labor is not entirely protective against pelvic floor disorders. LEVEL OF EVIDENCE: II-3.     

Mode of delivery and fecal incontinence at midlife: a study of 2,640 women in the Gazel cohort

OBJECTIVE: To estimate obstetric risk factors of fecal incontinence among middle-aged women. METHODS: We conducted a mail survey of the Gazel cohort of volunteers for epidemiologic research. In 2000, a questionnaire on anal incontinence was mailed to 3,114 women who were then between the ages of 50 and 61 years; 2,640 (85%) women returned the completed questionnaire. Fecal incontinence was defined by involuntary loss of stool. Logistic regression was used to estimate the effect of obstetric and general risk factors. RESULTS: Prevalence of fecal incontinence in the past 12 months was 9.5% (250). Significant risk factors for fecal incontinence were completion of high school (adjusted odds ratio [OR] 1.5, 95% confidence interval [CI] 1.1-2.0), self-reported depression (OR 2.1, 95% CI 1.6-2.7), overweight or obesity measured by body mass index (BMI) (OR 1.5 for BMI of 25-30, 95% CI 1.1-2.0; OR 1.6 for BMI more than 30, 95% CI 1.1-2.5), surgery for urinary incontinence (OR 3.5, 95% CI 2.0-6.1), and anal surgery (OR 1.7, 95% CI 1.1-2.9). No obstetric variable (parity, mode of delivery, birth weight, episiotomy, or third-degree perineal tear) was significant. Prevalence of fecal incontinence was similar for nulliparous, primiparous, secundiparous, and multiparous women (11.3%, 9.0%, 9.0%, and 10.4%, respectively), and among parous women, it was similar for women with spontaneous vaginal, instrumental (at least one), or only cesarean deliveries (9.3%, 10.0%, and 6.6%, respectively). CONCLUSION: In our population of women in their 50s, fecal incontinence was not associated with either parity or mode of delivery.     

Anal incontinence after vaginal delivery: a prospective study in primiparous women

Objective To investigate the incidence and degree of anal incontinence after vaginal delivery among primiparous women and to define associated risk factors.
Design Prospective observational study.
Setting Karolinska Institutet, Danderyd Hospital, Sweden, a university hospital.
Participants Three hundred and forty-nine primiparous women.
Methods Questionnaires distributed within the first days after delivery and re-distributed five and nine months postpartum. Analysis of delivery records.
Results Eighty percent of the women answered all questionnaires. At five months postpartum, 2% of the women had symptoms of faecal incontinence and 25% had symptoms of involuntary flatus. At nine months postpartum, 1 % of the women had symptoms of faecal incontinence and 26% had symptoms of involuntary flatus. The majority of the women had infrequent symptoms and a decrease in severity was noted at nine months. Symptoms of incontinence were more common in women who sustained a sphincter tear at delivery. Risk factors for incontinence at five months included maternal age, duration of the second stage of labour, instrumental vaginal delivery, and clinically diagnosed sphincter tear at delivery. Development of incontinence at nine months was associated with maternal age and clinically diagnosed sphincter tear at delivery.
Conclusions The present study demonstrates that infrequent involuntary flatus is a common symptom after vaginal delivery in primiparous women. These symptoms of involuntary flatus frequently improved and only a few women suffered from frank faecal incontinence. Factors associated with an increased risk of anal incontinence and sphincter tears should be considered during delivery.     

Anal incontinence after vaginal delivery: a prospective study in primiparous women.

OBJECTIVE: To investigate the incidence and degree of anal incontinence after vaginal delivery among primiparous women and to define associated risk factors. DESIGN: Prospective observational study. SETTING: Karolinska Institutet, Danderyd Hospital, Sweden, a university hospital. PARTICIPANTS: Three hundred and forty-nine primiparous women. METHODS: Questionnaires distributed within the first days after delivery and re-distributed five and nine months postpartum. Analysis of delivery records. RESULTS: Eighty percent of the women answered all questionnaires. At five months postpartum, 2% of the women had symptoms of faecal incontinence and 25% had symptoms of involuntary flatus. At nine months postpartum, 1% of the women had symptoms of faecal incontinence and 26% had symptoms of involuntary flatus. The majority of the women had infrequent symptoms and a decrease in severity was noted at nine months. Symptoms of incontinence were more common in women who sustained a sphincter tear at delivery. Risk factors for incontinence at five months included maternal age, duration of the second stage of labour, instrumental vaginal delivery, and clinically diagnosed sphincter tear at delivery. Development of incontinence at nine months was associated with maternal age and clinically diagnosed sphincter tear at delivery. CONCLUSIONS: The present study demonstrates that infrequent involuntary flatus is a common symptom after vaginal delivery in primiparous women. These symptoms of involuntary flatus frequently improved and only a few women suffered from frank faecal incontinence. Factors associated with an increased risk of anal incontinence and sphincter tears should be considered during delivery.     

Flatus and faecal incontinence: prevalence and risk factors at 16 weeks of gestation

Objective To evaluate the prevalence of anal incontinence at 16 weeks of gestation and to identify possible maternal and obstetrical risk factors.
Design Cross sectional study and cohort study.
Setting Department of Obstetrics and Gynaecology, Aarhus University Hospital, Denmark.
Participants Cross sectional study: 7557 women attending antenatal care. Cohort study: a subgroup of 1726 pregnant women with one previous delivery at our department.
Results The prevalence of anal incontinence within the preceding year was 8.6%. Incontinence of liquid and solid stools was reported in 2.3% and 0.6%, respectively. Isolated flatus incontinence at least once a week was reported in 4.2%. The risk of flatus incontinence at least once a week was increased with age > 35 years (OR 1.6; 95% CI 1.1–2.4) and with previous lower abdominal or urological surgery (OR 1.5, 95% CI 1.1–2.1) in a logistic regression model controlling for maternal factors. Increasing parity did not increase the risk. The risk of flatus incontinence was increased after anal sphincter tear and birthweight > 4000 g in a logistic regression model controlling for maternal and obstetric variables. Episiotomy was insignificantly associated, while spontaneous perineal tear > 3 cm and a number of other intrapartum factors were not associated.
Conclusion True faecal incontinence is rare among younger women. However, an age > 35 years and previous lower abdominal or urological surgery increased the risk of flatus incontinence in contrast to increasing parity. This suggests that childbirth plays a minor role compared with age. However, when analysing obstetric variables separately, a birthweight > 4000 g, and anal sphincter tears were significant risk factors for flatus incontinence.     

Diagnosis of anal sphincter tears by postpartum endosonography to predict fecal incontinence

OBJECTIVE: To determine whether anal endosonography immediately after vaginal delivery can predict subsequent fecal incontinence. METHODS: We studied nulliparas who delivered vaginally and had no anal sphincter tears (third- or fourth-degree perineal tears) diagnosed clinically by endosonography before any suture of the perineum. The sonographer was unaware of delivery details and the obstetrician and the women were not informed of endosonography results. Therefore, the suture of the perineum and the outcomes were not influenced by sonographer's diagnoses. Three months after delivery, we assessed fecal incontinence by self-administered questionnaires. RESULTS: Clinically undetected tears of the anal sphincter were diagnosed by anal endosonography in 42 of 150 women (28%). The external anal sphincter alone was involved in 30 women (20%), the internal anal sphincter alone in two (1.3%), and both in ten (7%). The postal questionnaire was returned by 144 women. Incontinence was reported by 22 (15%, 95% confidence interval [CI] 10%, 22%), consisting mainly of incontinence to flatus only (16 of 22, 73%, 95% CI 50%, 89%). Clinically undetected anal sphincter tears diagnosed by endosonography were associated with incontinence 3 months after delivery (odds ratio [OR] 8.8; 95% CI 2.9, 26.5). The sensitivity of anal endosonography was 68% (95% CI 49%, 88%) and the positive predictive value 37% (95% CI 22%, 51%). CONCLUSION: Anal endosonography immediately after vaginal delivery allows diagnosis of clinically undetected anal sphincter tears that might be associated with subsequent fecal incontinence.     

Risk factors for anal sphincter tear in multiparas

OBJECTIVE: To assess maternal, newborn, and obstetric risk factors associated with anal sphincter tear in multiparous women. METHODS: This case-control study identified 18,779 multiparous vaginal deliveries from 1992 to 2004 from an obstetric automated record database at the University of Alabama at Birmingham. Two hundred eighty-four patients were selected, 145 cases and 139 controls. Variables from the index pregnancy and prior pregnancies were analyzed, and multivariable logistic regression models were constructed to determine significant predictor variables for anal sphincter tear in multiparous women. RESULTS: One hundred forty-five multiparous women with no history of cesarean delivery sustained a sphincter tear. Multivariable logistic regression showed a significant association with episiotomy (odds ratio [OR] 16.3, 95% confidence interval [CI] 7.7-34.4), shoulder dystocia (OR 7.9, CI 1.6-38), forceps delivery (OR 4.7, CI 2.0-11.2), and being married (OR 2.2, CI 1.1-4.6). A second exploratory model that included variables from previous pregnancies, showed that in addition to episiotomy (OR 34.6, CI 8.8-136), shoulder dystocia (OR 11.1, CI 1.3-95.2), forceps delivery (OR 6.1, CI 1.6-23.5), previous sphincter tear (OR 7.7, CI 1.2-48.7), and second stage of labor greater than 1 hour (OR 6.7, CI 1.1-42.5) were associated with tear. CONCLUSION: The strongest clinical risk factors for anal sphincter tear in multiparous women are episiotomy, shoulder dystocia, previous sphincter tear, prolonged second stage of labor, and forceps delivery. LEVEL OF EVIDENCE: II-2.     

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.     

Risk factors for anal sphincter tear during vaginal delivery

OBJECTIVE: To identify risk factors associated with anal sphincter tear during vaginal delivery and to identify opportunities for preventing this cause of fecal incontinence in young women. METHODS: We used baseline data from two groups of women who participated in the Childbirth and Pelvic Symptoms (CAPS) study: those women who delivered vaginally, either those with or those without a recognized anal sphincter tear. Univariable analyses of demographic and obstetric information identified factors associated with anal sphincter tear. We calculated odds ratios (ORs) for these factors alone and in combination, adjusted for maternal age, race, and gestational age. RESULTS: We included data from 797 primaparous women: 407 with a recognized anal sphincter tear and 390 without. Based on univariable analysis, a woman with a sphincter tear was more likely to be older, to be white, to have longer gestation or prolonged second stage of labor, to have a larger infant (birth weight/head circumference), or an infant who was in occiput posterior position, or to have an episiotomy or operative delivery. Logistic regression found forceps delivery (OR 13.6, 95% confidence interval [CI] 7.9-23.2) and episiotomy (OR 5.3, 95% CI 3.8-7.6) were strongly associated with a sphincter tear. The combination of forceps and episiotomy was markedly associated with sphincter tear (OR 25.3, 95% CI 10.2-62.6). The addition of epidural anesthesia to forceps and episiotomy increased the OR to 41.0 (95% CI 13.5-124.4). CONCLUSION: Our results highlight the existence of modifiable obstetric interventions that increase the risk of anal sphincter tear during vaginal delivery. Our results may be used by clinicians and women to help inform their decisions regarding obstetric interventions. LEVEL OF EVIDENCE: II.     

Obstetric sphincter tears and anal incontinence: an observational follow-up study

BACKGROUND: Persistent defects after primary sphincter repair and occult sphincter tears are common after vaginal deliveries. Anal incontinence may be associated with these morphological defects. MATERIAL AND METHODS: Forty-six primiparous women were evaluated with ultrasonography, manometry and electrophysiology. Twenty-four women had undergone primary repair of obstetric sphincter tears (sphincter group), 16 women had no clinical sphincter tear but developed anal incontinence postpartum (symptom group), and six were delivered by elective cesarean section (cesarean group). RESULTS: In the sphincter group, 50% had anal incontinence at follow-up. At ultrasonography, 70% had injuries anteriorly in the midanal canal. At manometry, 4% had decreased resting pressure and 50% decreased squeeze pressure. At electrophysiology, 19% had pathologic pudendal latency and 25% pathologic fiber density. In the symptom group, 44% had injuries anteriorly in the midanal canal at ultrasonography. At manometry, all women had normal resting pressure and 19% had a decreased squeeze pressure. At electrophysiology, 46% had pathologic pudendal latency and 29% pathologic fiber density. In the cesarean group, 33% had mild anal incontinence at follow-up. Ultrasonography and manometry were normal in all women. At electrophysiology, 33% had pathologic pudendal latency and 17% pathologic fiber density. CONCLUSION: Anal sphincter injuries at childbirth are often inadequately diagnosed and primary repair frequently results in persisting defects in the anal sphincter. Anatomic injuries to the anal sphincter play an important role in the development of anal incontinence after delivery, but a significant proportion of symptomatic women also demonstrate neurologic impairment at electrophysiologic testing.     

Recurrent risk of anal sphincter laceration among women with vaginal deliveries

OBJECTIVE: The first aim of this study was to estimate the impact of anal sphincter laceration during the first delivery on the risk of recurrence in the second delivery. The second aim was to estimate the absolute risk of anal sphincter laceration in the second delivery according to the history of anal sphincter laceration and birth weight. METHODS: In this population-based cohort study, the study sample comprised all women included in the Norwegian Medical Birth Registry with 2 consecutive singleton vaginal deliveries during the period 1967-1998 (n = 486,463). The impact of prior anal sphincter laceration on recurrent anal sphincter laceration was estimated as crude and adjusted odds ratios (ORs). RESULTS: Anal sphincter laceration during first delivery increased the risk for a sphincter laceration in the next delivery, (adjusted OR 4.3, 95% confidence interval [CI] 3.8-4.8). Other risk factors were birth weight (adjusted OR 23.6, 95% CI 16.5-33.6, birth weight > 5,000 g versus birth weight < 3,000 grams), use of forceps (adjusted OR 5.1, 95% CI 4.3-6.0), use of vacuum (adjusted OR 1.4, 95% CI 1.1-1.7), and period of delivery (adjusted OR 4.3, 95% CI 3.7-5.0 for 1995-1998 versus 1967-1975). The absolute risks for anal sphincter laceration at second delivery for women with prior laceration were 1.3% (95% CI 0.4-3.2%) for birth weight less than 3,000 g and 23.3% (95% CI 11.8-38.6%) for birth weight more than 5,000 g. CONCLUSION: Only 10% of women with anal sphincter laceration at second delivery had a history of prior laceration. Prior anal sphincter laceration is associated with increased risk of laceration in second delivery, in particular in women who carry children with high birth weight. LEVEL OF EVIDENCE: II-2.     

Postpartum sphincter rupture and anal incontinence: prospective study with 259 patients

AIMS: Damage to the anal sphincter has been considered as the cause of anal incontinence after childbirth. The aims of the present study were to determine prospectively the incidence of anal incontinence and anal sphincter damage after childbirth, and their relationship with obstetric parameters in France. PATIENTS AND METHODS: We studied 259 consecutive women six weeks before and eight weeks after delivery. They were asked to fill out a questionnaire dealing with faecal and urinary incontinence. Anal endosonography (B&K 7-10 MHz) was then performed. Two independent observers analyzed internal and external anal sphincters. RESULTS: Two hundred and thirty-three women (90%) were assessed, among whom 31 had had a caesarean section. De novo sphincter defects were observed in 19.3% (39 patients) in the postpartum period only after vaginal delivery (202 patients). These disruptions occurred with the same incidence after the first and second childbirth. Independent risk factors (odds ratio; 95% confidence interval) for sphincter defect were forceps (odds ratio 11.9; 4.8-33.3), perineal tears (odds ratio 16.1; 4.4-83.9), episiotomy (odds ratio 6.6; 1.7-34.2), and pauciparity < or = 2 (odds ratio 8.8; 1-78.3), as revealed by multivariate analyses. The overall rate of de novo anal incontinence was 9% (20 patients), and independent risk factors involved forceps (odds ratio 4.5; 1.5-13), perineal tears (odds ratio 3.9; 1.4-10.9), de novo sphincter defect (odds ratio 5.5; 5-15) and prolonged labor (odds ratio 3.4; 1-11). Among the 20 women who had de novo anal incontinence, only 45% (9 patients) had sphincter defects. CONCLUSION: De novo anal incontinence after delivery is multifactorial and anal sphincter defects account only for 50% of them. Primiparous and secundiparous women have the same high-risk factor for sphincter disruption and anal incontinence. Since external anal sphincter disruptions are more frequent than internal anal sphincter damage, surgical repair should be discussed.     

Symptoms of stress incontinence 1 year after childbirth: prevalence and predictors in a national Swedish sample

BACKGROUND: The aims of the present study were to describe the prevalence of stress incontinence, as described by women themselves, 1 year after childbirth in a national sample of Swedish-speaking women, and to identify possible predictors. METHODS: A cohort study, including 2390 women recruited from 593 antenatal clinics in Sweden during three 1-week periods evenly spread over 1 year (1999-2000), representing 53% of women eligible for the study and 75% of those who consented to participate. Data were collected by means of questionnaires in early pregnancy, 2 months and 1 year after the birth, and from the Swedish Medical Birth Register. RESULTS: One year after the birth, 22% of the women had symptoms of stress incontinence but only 2% said it caused them major problems. The strongest predictor was urinary incontinence (overall leakage) 4-8 weeks after a vaginal delivery (OR 5.5, CI 95% 4.1-7.4) as well as after a cesarean section (OR 11.9, CI 95% 2.9-48.1). Other predictors in women with a vaginal delivery were: multiparity (OR 1.4; CI 95% 1.1-1.8), obesity (OR 1.6; CI 95% 1.1-2.4) and constipation 4-8 weeks postpartum (OR 1.4; CI 95% 1.1-1.9). CONCLUSION: Stress incontinence 1 year after childbirth is a common symptom, which could possibly be reduced by identifying women with urinary leakage at the postnatal check-up.