Preserving the pelvic floor and perineum during childbirth--elective caesarean section?

Childbirth-induced trauma to the urethral continence mechanism: review and recommendations

To summarize the literature on immediate pelvic floor damage from childbirth and episiotomy, a MEDLINE search of English language articles published from 1983 to 2001 was performed. Vaginal delivery causes varying degrees of muscular, neuromuscular, and connective tissue damage. This damage may result in urinary and/or fecal incontinence. Routine midline episiotomy increases the risk of third- and fourth-degree perineal lacerations, which may lead to fecal incontinence. Routine use of mediolateral episiotomy does not prevent urinary incontinence (UI) or severe perineal tears. It is possible to reduce the rate of mediolateral episiotomy to as low as 20% in primiparas without increasing the risk of anal sphincter damage. Control of obesity before delivery, as well as pelvic floor exercises and regular physical exercise both before and after delivery, seem to reduce the risk of postpartum UI.

Cesarean section for non-medical reasons

Cesarean section without medical indication is cited as a factor in the increase in the rate of cesarean delivery in modern obstetric practice. Individual obstetricians often express strong views supporting or refuting the right of women to request operative delivery and their rights to decline or fulfill this request. Such strong opinions may be misplaced as the available evidence does not conclusively support either view-point.

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.

Trends in major risk factors for anal sphincter lacerations: a 10-year study

OBJECTIVES

(1) To identify independent risk factors for anal sphincter laceration, (2) to determine the trend in rates of anal sphincter laceration over a 10-year period, and (3) to examine the impact of temporal trends in risk factors on anal sphincter laceration rates.

METHODS

Population-based data were obtained from the Nova Scotia Atlee Perinatal Database, on 91 206 women who had a singleton vaginal live birth > or =500 g for the years 1988 to 1997. Risk factors for anal sphincter laceration were identified using stepwise logistic regression. A multivariate model was used to study temporal changes in laceration rates after controlling for changes in parity, episiotomy rates, operative vaginal deliveries, birth weight, prolonged second stage of labour, and other determinants.

RESULTS

Nulliparity (relative risk [RR] = 6.97), occiput posterior position (RR = 2.44), non-vertex presentations (RR = 2.27), second stage > or =120 min (RR range = 1.47-2.02), delivery by an obstetrician (RR = 1.30), and birth weight > or =3000 g (RR range = 1.43-6.63) increased the risk of laceration. Instrument-assisted delivery involved risks that ranged from a 2-fold increase for a vacuum-assisted delivery (RR = 2.15) to a greater than 5-fold increase for a forceps delivery after an unsuccessful vacuum extraction (RR = 5.69). Episiotomy, particularly midline incisions, increased the risk of laceration (RR = 2.57). The risk of a sphincter laceration increased 2-fold from 1988 to 1997, despite controlling for risk factors.

CONCLUSIONS

Sufficient evidence exists about the risk factors for anal sphincter laceration to permit modification of management of labour and delivery to minimize the risk of anal sphincter laceration. Increased awareness of the clinical importance of recognition and repair of anal sphincter laceration may explain the rising incidence.

Differential gene expression in pubococcygeus muscle from patients with pelvic organ prolapse

OBJECTIVE

This study was undertaken to compare differential gene expression in the pubococcygeus muscle in patients with pelvic organ prolapse and controls.

STUDY DESIGN

We performed microarray analysis on individual pubococcygeus muscle biopsy specimens from five patients with stage III or IV pelvic organ prolapse and five control subjects without prolapse. This study received full Institutional Review Board approval. Total RNA was extracted, purified, and probed on the Human Genome U95A Array for each individual sample. RNA from patients and controls was not pooled. For microarray analysis, 7 microg of total RNA was used to synthesize complementary DNA that was then biotinylated. Arrays were hybridized for 16 hours in the GeneChip Fluidics Station 400 and were washed and scanned with the Hewlett-Packard GeneArray Scanner. Affymetrix GeneChip 5.0 software was used for scanning and data analysis.

RESULTS

Of the 12626 total genes compared, 257 genes were more than 2-fold underexpressed, 20 genes were more than 5-fold underexpressed, and 3 genes were more than 10-fold underexpressed in patients with pelvic organ prolapse compared with control subjects. Myosin-binding protein H was 24.7 times underexpressed in patients with prolapse (normalized signal intensity [NSI]: 0.46 [0.2-0.6]) compared with controls (NSI: 11.4 [0.2-31.3]). Skeletal muscle myosin heavy polypeptide 3 was 17.4 times underexpressed in patients with prolapse (NSI: 0.85 [0.7-0.9]) compared with controls (NSI: 14.8 [1.5-38.3]). Of the 12,626 genes compared, 479 genes were more than 2-fold overexpressed, 18 genes were more than 5-fold overexpressed, and 2 genes were more than 10-fold overexpressed in patients with pelvic organ prolapse compared with controls. Many of these overexpressed genes were related to actin and myosin proteins. Smooth muscle myosin heavy chain was 11.8 times overexpressed in patients (NSI: 5.21 [0.25-22.71]) compared with controls (NSI 0.44 [0.11-0.71]). Myosin light-chain kinase was 5.8 times overexpressed in patients (NSI: 7.9 [0.5-36.1]) compared with controls (NSI: 1.37 [0.38-1.8]). Extracellular matrix proteins were also differentially regulated. Cartilage oligomeric matrix protein precursor was found to be 6.0 times underexpressed, whereas tenascin-C (hexabrachion) was 5.1 times overexpressed in prolapse patients.

CONCLUSION

These data suggest that the differences between patients with advanced pelvic organ prolapse and controls may be related to differential gene expression of structural proteins that are related to actin and myosin as well as extracellular matrix proteins in the pubococcygeus muscle. Studies are ongoing to confirm these findings and to further characterize the role of these genes in prolapse.

Scottish female obstetricians' views on elective caesarean section and personal choice for delivery

We have been reminded many times in the medical and lay press about the views of London female obstetricians choosing elective caesarean section for non-medical reasons. This paper asked Scottish female obstetricians for their personal choice regarding delivery and showed that only 15.5% would choose elective caesarean section compared with 31% and 21% in two surveys of London female obstetricians. None of the women in this group who had had a vaginal delivery would choose elective section.

Informed consent and birth: protecting the pelvic floor and ourselves

The controversy over elective cesarean versus vaginal birth with regard to pelvic floor trauma has left many caregivers and patients confused. With the growing evidence to support the development of fecal incontinence as a result of childbirth, we believe that it is imperative to reevaluate modern obstetric practices both for the patient's benefit and for our medical-legal protection. Our attention and energy need to be focused on good informed consent regarding these risks along with improved postpartum surveillance for injury.

Anatomy and physiology of the female perineal body with relevance to obstetrical injury and repair

The female perineal body is a mass of interlocking muscular, fascial, and fibrous components lying between the vagina and anorectum. The perineal body is also an integral attachment point for components of the urinary and fecal continence mechanisms, which are commonly damaged during vaginal childbirth. Repair of injuries to the perineal body caused by spontaneous tears or episiotomy are topics too often neglected in medical education. This review presents the anatomy and physiology of the female perineal body, as well as clinical considerations for pelvic reconstructive surgery.

Prevalence and persistence of health problems after childbirth: associations with parity and method of birth

BACKGROUND

Awareness about the extent of maternal physical and emotional health problems after childbirth is increasing, but few longitudinal studies examining their duration have been published. The aim of this study was to describe changes in the prevalence of maternal health problems in the 6 months after birth and their association with parity and method of birth.

METHODS

A population-based, cohort study was conducted in the Australian Capital Territory (ACT), Australia. The study population, comprising women who gave birth to a live baby from March to October 1997, completed 4 questionnaires on the fourth postpartum day, and at 8, 16, and 24 weeks postpartum. Outcome measures were self-reported health problems during each of the three 8-week postpartum periods up to 24 weeks.

RESULTS

A total of 1295 women participated, and 1193 (92) completed the study. Health problems showing resolution between 8 and 24 weeks postpartum were exhaustion/extreme tiredness (60-49), backache (53-45), bowel problems (37-17), lack of sleep/baby crying (30-15), hemorrhoids (30-13), perineal pain (22-4), excessive/prolonged bleeding (20-2), urinary incontinence (19-11), mastitis (15-3), and other urinary problems (5-3). No significant changes occurred in the prevalence of frequent headaches or migraines, sexual problems, or depression over the 6 months. Adjusting for method of birth, primiparas were more likely than multiparas to report perineal pain and sexual problems. Compared with unassisted vaginal births, women who had cesarean sections reported more exhaustion, lack of sleep, and bowel problems; reported less perineal pain and urinary incontinence in the first 8 weeks; and were more likely to be readmitted to hospital within 8 weeks of the birth. Women with forceps or vacuum extraction reported more perineal pain and sexual problems than those with unassisted vaginal births after adjusting for parity, perineal trauma, and length of labor.

CONCLUSIONS

Health problems commonly occurred after childbirth with some resolution over the 6 months postpartum. Some important differences in prevalence of health problems were evident when parity and method of birth were considered.

Management of obstetric anal sphincter injury: a systematic review & national practice survey

BACKGROUND

We aim to establish the evidence base for the recognition and management of obstetric anal sphincter injury (OASI) and to compare this with current practice amongst UK obstetricians and coloproctologists.

METHODS

A systematic review of the literature and a postal questionnaire survey of consultant obstetricians, trainee obstetricians and consultant coloproctologists was carried out.

RESULTS

We found a wide variation in experience of repairing acute anal sphincter injury. The group with largest experience were consultant obstetricians (46.5% undertaking > or = 5 repairs/year), whilst only 10% of responding colorectal surgeons had similar levels of experience (p < 0.001). There was extensive misunderstanding in terms of the definition of obstetric anal sphincter injuries. Overall, trainees had a greater knowledge of the correct classification (p < 0.01). Observational studies suggest that a new 'overlap' repair using PDS sutures with antibiotic cover gives better functional results. However, our literature search found only one randomised controlled trial (RCT) on the technique of repair of OASI, which showed no difference in incidence of anal incontinence at three months. Despite this, there was a wide variation in practice, with 337(50%) consultants, 82 (55%) trainees and 80 (89%) coloproctologists already using the 'overlap' method for repair of a torn EAS (p < 0.001). Although over 50% of colorectal surgeons would undertake long-term follow-up of their patients, this was the practice of less than 10% of obstetricians (p < 0.001). Whilst over 70% of coloproctologists would recommend an elective caesarean section in a subsequent pregnancy, only 22% of obstetric consultants and 14% of trainees (p < 0.001).

CONCLUSION

An agreed classification of OASI, development of national guidelines, formalised training, multidisciplinary management and further definitive research is strongly recommended.

Suspected big baby: a difficult clinical problem in obstetrics

BACKGROUND

Large for gestational age fetuses, also called macrosomic fetuses, represent a continuing challenge in obstetrics.

METHODS

We review various problems with large for gestational age fetuses. We have performed a literature search, mainly through the database PubMed (includes the Medline database). The clinical problem is discussed from the primary care provider's, the patient's and the obstetrician's point of view.

RESULTS

Macrosomia is arbitrarily defined as having a fetal weight of above the 90th percentile, a birth weight of above 4000 g or 4500 g, or a birth weight of over +2 standard deviation of the mean birth weight by gestational age. The diagnosis of macrosomia is difficult, both by palpation and symphysis fundus measurement; even with sophisticated sonographic measures. The combination of biparietal diameter, femur length and abdominal circumference appears to be no better than abdominal circumference alone.

INTERPRETATION

Based on the literature, labor should not be induced in nondiabetic pregnancies. The best policy is to await spontaneous birth or to induce labor after 42 weeks completion. A great number of cesarean sections have to be performed to avoid a single case of plexus brachialis paresis resulting from a difficult shoulder delivery. Cesarean section should not be considered in nondiabetic pregnancies unless the estimated fetal weight is above 5000 g. In pregnancies complicated by diabetes mellitus there are reasons for selective induction of labor if macrosomia is suspected and for cesarean section if the calculated birth weight is above 4000 g. Each department should have a strategy to handle such a situation because the problem with the difficult shoulder delivery cannot be completely avoided. Different procedures of managing difficult shoulder delivery are described.

Antenatal screening for postpartum urinary incontinence in nulliparous women: a pilot study

Antenatal screening for postpartum urinary incontinence in nulliparous women: a pilot study.

OBJECTIVE

To examine the utility of joint mobility scoring (JMS) as a screening test for postpartum urinary incontinence.

STUDY DESIGN

A prospective cohort study in a teaching hospital involving 150 nulliparous women. JMS was calculated. The incidence of incontinence and pad use was recorded. Univariate and multiple logistic regression analyses were used to identify factors independently associated with incontinence.

RESULTS

Hundred and three women completed the study. 43.7% of subjects were incontinent antenatally and 4.9% remained incontinent at the study end. JMS was normally distributed and similar in continent and incontinent women. Elbow hyperextension (>180 degrees ) was associated with postnatal incontinence (odds ratio 10.6; 95% CI 1.24, 90.8). Elbow hyperextension had a sensitivity of 80%, specificity of 75%, positive predictive value of 14%, and negative predictive value of 99% for postnatal incontinence.

CONCLUSION

Joint hypermobility score is not a useful screening test. Elbow hyperextension is associated with an increased likelihood of postnatal urinary incontinence. It is unclear whether this test has clinical utility outside a research setting.

Lower genital tract and anal sphincter trauma

Anal incontinence occurs more frequently in women but its incidence is grossly underestimated because of under-reporting. Obstetric trauma is a major cause of anal incontinence but it is only recently that attention has been focused on this subject. Episiotomy and choice of instrument at assisted delivery have been subjected to randomized trials but some issues, such as the benefit of episiotomy in instrumental delivery, have not been addressed. The management of acute anal sphincter rupture is inconsistent and, although studies report on the sub-optimal outcome, evidence-based guidelines are currently awaiting publication. Training in perineal anatomy and repair is poorly taught, and there is wide variation in classification of perineal tears. Consequently anal sphincter tears are being missed at delivery and/or inappropriately managed. This chapter aims to highlight these issues based on previous and current teaching and to recommend a protocol based on the best available evidence.

Vacuum-assisted delivery

Unsuccessful vacuum extraction, cup detachment and failed anterior rotation in occipitoposterior positions are commonly associated with obstetric factors that are avoidable or correctable. These factors include the preferential use of soft vacuum cups, incorrect cup applications and attempts to deliver with the vacuum extractor before the cervix is completely dilated. Evidence from randomized trials demonstrates that soft cups cause fewer cosmetic effects and scalp lacerations than rigid cups. Soft cups do not reduce the incidence of cephalhaematomas nor have they been shown to provide any advantage over rigid cups for the prevention of subgaleal haemorrhage. Clinically significant subgaleal haemorrhage and intracranial injury are almost always preceded by difficult vacuum extraction. Although the vacuum extractor is less likely than forceps to injure the mother's genital tract and anal sphincters at delivery, no significant differences have been demonstrated between the instruments in terms of subsequent urinary or bowel disturbances.

Anatomical and physiological characteristics of perineal muscles in the female rabbit

Little information is available on the participation of the perineal striated muscles in female reproductive processes. Here, we describe the gross anatomy and innervation of two striated perineal muscles in the female rabbit, the bulbospongiosus (BSM) and ischiocavernosus (ISM), and analyze their reflex electromyographic (EMG) activity in response to stimulation of the perigenital skin and vaginal tract. Twenty-four mature chinchilla-breed rabbit does were used: 12 to describe the anatomy and innervation of the muscles, 9 to determine reflex EMG activity of the muscles in response to stimulation of the perigenital skin and specific levels of the vaginal tract and 3 to analyze the effect of contraction of the muscles on intravaginal pressure. Both muscles were well developed, with their fibers originating at the ischiadic arch and inserting onto the ligamentum suspensorium clitoridis. Branches of the clitoral and perineal nerves innervated the BSM and ISM, respectively. Bilateral electrical stimulation of these nerves provoked retraction of the clitoral sheath and an increase in intravaginal pressure at the level of the perineal vagina. Whereas neither muscle responded to stimulation of the perigenital skin, both were reflexively activated during mechanical stimulation of the inner walls of the perineal vagina. Prolonged cervical stimulation inhibited this reflex. Thus, in reproductive processes such as copulation and/or parturition, the contraction of these muscles may be induced during stimulation of the perineal vagina.

Achieving sustainable quality in maternity services - using audit of incontinence and dyspareunia to identify shortfalls in meeting standards

BACKGROUND: Some complications of childbirth (for example, faecal incontinence) are a source of social embarrassment for women, and are often under reported. Therefore, it was felt important to determine levels of complications (against established standards) and to consider obstetric measures aimed at reducing them. METHODS: Clinical information was collected on 1036 primiparous women delivering at North and South Staffordshire Acute and Community Trusts over a 5-month period in 1997. A questionnaire was sent to 970 women which included self-assessment of levels of incontinence and dyspareunia prior to pregnancy, at 6 weeks post delivery and 9 to 14 months post delivery. RESULTS: The response rate was 48%(470/970). Relatively high levels of obstetric interventions were found. In addition, the rates of instrumental deliveries differed between the two hospitals. The highest rates of postnatal symptoms had occurred at 6 weeks, but for many women problems were still present at the time of the survey. At 9-14 months high rates of dyspareunia (29%(102/347)) and urinary incontinence (35%(133/382)) were reported. Seventeen women (4%) complained of faecal incontinence at this time. Similar rates of urinary incontinence and dyspareunia were seen regardless of mode of delivery. CONCLUSION: Further work should be undertaken to reduce the obstetric interventions, especially instrumental deliveries. Improvements in a number of areas of care should be undertaken, including improved patient information, improved professional communication and improved professional recognition and management of third degree tears. It is likely that these measures would lead to a reduction in incontinence and dyspareunia after childbirth.

Anal function: effect of pregnancy and delivery

OBJECTIVE

To investigate the effect of pregnancy and delivery on anal continence, sensation, manometry, and sphincter integrity.

STUDY DESIGN

Two hundred eighty-six nulliparous women in the third trimester completed a symptom questionnaire and underwent anorectal sensation and manometric evaluations. Three months postpartum, 161 women returned and the questionnaires and investigations were repeated together with anal endosonographic examinations.

RESULTS

The prevalence of fecal urgency before, during, and after pregnancy was 1%, 9.4%, and 10.5%, respectively; the prevalence of anal incontinence before, during, and after pregnancy was 1.4%, 7.0%, and 8.7%, respectively. Vaginal delivery, particularly instrumental, resulted in a decrease in anal squeeze pressures (P =.015) and resting pressures (P =.002) but had no effect on anal sensation. Postpartum anal endosonographic examination revealed sphincter disruption in 38% of women. There was no relationship between symptoms and anal manometry, sensation, or sphincter integrity. Vaginal delivery (P <.0001) and perineal trauma (P <.001) were significantly associated with sphincter defects.

CONCLUSION

Vaginal delivery is associated with a decrease in anal pressures and increased anal sphincter trauma but has no effect on anal sensation. These changes were not related to anal symptoms.

The management of the second stage of labor

OBJECTIVE

To review obstetric practice in a single maternity hospital with respect to the assisted vaginal delivery rate.

METHOD

A retrospective analysis of the hospital statistics, labor ward records, casenotes and management protocols with respect to the second stage of labor was performed in a single maternity unit in the UK; the study included 43352 women who delivered a baby between the years of 1987 and 1997. The study looked at the rate of assisted vaginal deliveries, cesarean section, epidural in labor, and as well as the perinatal mortality rate.

RESULTS

In the 11-year period of the study, 43352 women delivered with a mean assisted vaginal delivery rate of 3.70%, cesarean section rate of 12.4% and an epidural rate of 31.5%.

CONCLUSION

The management of the second stage of labor in this unit results in an assisted vaginal delivery rate significantly below the national average. The authors highlight the paucity of research in this important area of practice.

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.

Counselling women about choice

Patient choice-informed consent and informed refusal-is an important ethical and legal principle in medicine. In pregnancy this issue is not straightforward: should a pregnant woman's autonomous choice be respected when she may cause fetal harm by declining recommended caesarean section? Should a pregnant women be free to choose elective caesarean section as an alternative to labour and vaginal delivery? This chapter reviews cases of court-ordered caesarean, and the ethical and legal paradigms for informed refusal in pregnancy. In general, clinicians should not seek court authority to support medical recommendations. This chapter also reviews arguments for and against offering women elective caesarean without strict medical indication. Although compelling arguments in favour of caesarean on demand can be made, clear evidence showing adequate safety and advantages of elective caesarean over vaginal delivery does not yet exist. Ethics, law, politics and history all inform the issue of choice with respect to caesarean in important ways.

Can we reduce the caesarean section rate?

Caesarean section rates continue to be an issue of great concern to many midwives, obstetricians, women, and society as a whole. With an increase in women requesting caesarean sections, the responsibility for the caesarean section rate needs to be re-defined. There is a need to improve the routine information collection on all aspects of childbirth. There is also a need to adopt standard classification systems so that comparisons and improvement of care can take place. Caesarean section rates should no longer be thought of as being too high or too low, but rather whether they are appropriate or not, after taking into consideration all the relevant information. This will require statutory, standardized collection of information. Maternal satisfaction has now become one of the most significant outcome factors after childbirth and must be taken into consideration when implementing any changes in childbirth. Finally, caesarean section rates must no longer be considered in isolation from other changes taking place in society.

The effects of childbirth on the pelvic-floor

Basically, vaginal delivery is associated with the risk of pelvic floor damage. The pelvic floor sequelae of childbirth includes anal incontinence, urinary incontinence and pelvic organ prolapse. Pathophysiology, incidence and risk factors for the development of the respective problems are reviewed. Where possible, recommendations for reducing the risk of pelvic floor damage are given.

Vaginal birth and perineal trauma

Vaginal birth has been recognized as being potentially traumatic to the pelvic floor. It is important that contributory obstetric factors are identified and their occurrence minimized. Women who have sustained significant anal sphincter injury are at greater risk of further damage and faecal incontinence with subsequent deliveries. This review reports on recent developments in this field, and examines ways in which morbidity might be reduced.

CAESAREAN SECTION ON REQUEST

Advances in surgical techniques, anaesthesia, thromboprophylaxis, blood transfusion, antibiotic therapy, and improved general health have changed Caesarean section (CS) from a procedure associated with considerable risk of morbidity and mortality to mother and/or fetus to one with little risk. Although CS is performed for obstetric indications, the threshold is lower, including CS on request, leading to a trend of rising CS rates. A main focus of debate is CS request by women who subjectively perceive benefit from an elective CS. The issues involved are complicated and the implications far-reaching. When risks, benefits, and costs are assessed, the perceived advantage of vaginal delivery over elective CS may be diminished or eliminated and decisions on the mode of delivery may be based on preferences rather than statistics. In this article, we outline some of the arguments for and against CS on request and the opinion of the Ethics Committee of the International Federation of Obstetricians and Gynaecologists (FIGO).

Anorectal physiological testing before and after a successful sphincter repair: a prospective study

OBJECTIVE

Anorectal physiological testing often yields contradictory results in patients with faecal incontinence. This prospective study aims to determine if there are any discriminatory changes in anorectal physiological testing after a successful sphincter repair for sphincter defects.

PATIENTS AND METHODS

From 1995 to 1998, 20 consecutive females who underwent a successful overlapping sphincter repair for sphincter defect were evaluated by anorectal manometry and neurophysiologic testing before and 2-4 months after surgery. The sphincter defect was diagnosed preoperatively by clinical and endosonographic examination, confirmed at surgery. The severity of faecal incontinence was evaluated using the Cleveland Clinic Continence Score (0-20): 0 being perfect continence, and 20 being complete incontinence.

RESULTS

Of 20 consecutive patients who were improved following direct sphincter repair, 12 had significant improvement with a median score of 3 (range 1-6), while eight had mild improvement with a median score of 9 (range 7-12). There was a significant improvement in the mean resting anal canal pressure (80 vs 50 mmHg; P=0.016), maximum squeeze anal canal pressure (120 vs 80 mmHg; P=0.0002) and functional anal canal length (3 vs 2 cm; P=0.0069) post-operatively, with significant improvement in faecal continence following sphincter repair. However, a mild improvement in faecal continence was not associated with any significant changes in the mean resting anal canal pressure (50 vs 40 mmHg; P=0.089), maximum squeeze anal canal pressures (100 vs 100 mmHg; P=0.19) or functional anal canal length (2 vs 2 cm; P=0.47).

CONCLUSION

Marked improvement of faecal continence after overlapping sphincter repair is reflected by a marked increase in the mean resting anal canal pressure, maximum squeeze anal canal pressures and functional anal canal length.

Anal sphincter tears: prospective study of obstetric risk factors

OBJECTIVE

To evaluate intrapartum risk factors for anal sphincter tear.

DESIGN

A prospective observational study.

SETTING

Delivery unit at the University Hospital in Göteborg, Sweden.

PARTICIPANTS

2883 consecutive women delivered vaginally during the period between 1995 and 1997. Information was obtained, from patient records and from especially designed protocols which were completed during and after childbirth.

MAIN OUTCOME MEASURES

Anal sphincter (third and fourth degree) tear.

RESULTS

Anal sphincter tear occurred in 95 of 2883 women (3.3%). Univariate analysis demonstrated that the risk of anal sphincter tear was increased by nulliparity, high infant weight, lack of manual perineal protection, deficient visualisation of perineum, severe perineal oedema, long duration of delivery and especially protracted second phase and bear down, use of oxytocin, episiotomy, vacuum extraction and epidural anaesthesia. After analysis with stepwise logistic regression, reported as odds ratio, 95% confidence interval, the following factors remained independently associated with anal sphincter tear: slight perineal oedema (0.40, 0.26-0.64); manual perineal protection (0.49, 0.28-0.86); short duration of bear down (0.47, 0.24-0.91); no visualisation of perineum (2.77, 1.36-5.63); parity (0.59, 0.40-0.89); and high infant weight (2.02, 1.30-3.16). Analysis of variance showed that manual perineal protection had a stronger influence on lowering the frequency, and lack of visualisation of perineum and infant weight had a stronger influence on raising the frequency, of anal sphincter tears in nulliparous compared with parous women.

CONCLUSIONS

Perineal oedema, poor ocular surveillance of perineum, deficient perineal protection during delivery, protracted final phase of the second stage, parity and high infant weight all constitute independent risk factors for anal sphincter tear. Such information is essential in order to reduce perineal trauma during childbirth.

Women's sexual health after childbirth

OBJECTIVE

To investigate the impact of childbirth on the sexual health of primiparous women and identify factors associated with dyspareunia.

DESIGN

Cross-sectional study using obstetric records, and postal survey six months after delivery.

SETTING

Department of Obstetrics and Gynaecology, St George's Hospital, London.

POPULATION

All primiparous women (n = 796) delivered of a live birth in a six month period.

METHODS

Quantitative analysis of obstetric and survey data.

MAIN OUTCOME MEASURES

Self reported sexual behaviour and sexual problems (e.g. vaginal dryness, painful penetration, pain during sexual intercourse, pain on orgasm, vaginal tightness, vaginal looseness, bleeding/irritation after sex, and loss of sexual desire); consultation for postnatal sexual problems.

RESULTS

Of the 484 respondents (61% response rate), 89% had resumed sexual activity within six months of the birth. Sexual morbidity increased significantly after the birth: in the first three months after delivery 83% of women experienced sexual problems, declining to 64% at six months, although not reaching pre-pregnancy levels of 38% . Dyspareunia in the first three months after delivery was, after adjustment, significantly associated with vaginal deliveries (P = 0 x 01) and previous experience of dyspareunia (P = 0 x 03). At six months the association with type of delivery was not significant (P = 0 x 4); only experience of dyspareunia before pregnancy (P < 0 x 0001) and current breastfeeding were significant (P = 0 x 0006). Only 15% of women who had a postnatal sexual problem reported discussing it with a health professional.

CONCLUSIONS

Sexual health problems were very common after childbirth, suggesting potentially high levels of unmet need.

Effect of second vaginal delivery on anorectal physiology and faecal continence: a prospective study

BACKGROUND

Because obstetric injury to the anal sphincters may be occult, and because the mechanism of injury differs between first and subsequent deliveries, we prospectively assessed the effects of first and second vaginal deliveries on anal physiology and continence.

METHODS

We undertook a prospective observational study of 59 previously nulliparous women through two successive vaginal deliveries by means of a bowel-function questionnaire, and an anorectal-physiology assessment, both antepartum and 6-12 weeks post partum.

FINDINGS

13 (22%) women reported altered faecal continence after their first vaginal delivery: eight had persistent symptoms during their second pregnancy, of whom seven deteriorated after the second delivery; five regained continence before their second pregnancy, but two became incontinent again after the second delivery. Five women developed incontinence for the first time after their second vaginal delivery, of whom three had occult primiparous sphincter injury. 20 (34%) women, seven of whom had no symptoms, had anal-sphincter injury as a result of their first delivery, but only two new injuries occurred after the second vaginal delivery (p=0.013). Although pudendal neuropathy was no more common after the second than after the first vaginal delivery (15 vs 19%, p=0.8), pudendal-nerve latency was longer after the second delivery (p=0.02).

INTERPRETATION

Primiparous women with persistent symptoms of altered faecal continence experience deterioration after a second vaginal delivery. Women with transient faecal incontinence or occult anal-sphincter injury after their first vaginal delivery are at high risk of faecal incontinence after a second vaginal delivery. The risk of mechanical anal sphincter injury is greatest after the first 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.

The rise in caesarean section rate: the same indications but a lower threshold

OBJECTIVE

To investigate the reasons for the rise in caesarean section rate and note any change in indications.

DESIGN

A retrospective, descriptive study comparing the years 1962 and 1992.

SETTING

A large city centre teaching hospital.

RESULTS

There was an overall increase in the caesarean section rate from 6-8% in 1962 to 18.1% in 1992. No single cause contributed more than 30% towards this increase. The main indications in both years were similar: failure to progress (42.2% vs 36.7%) and fetal indications (18.1% vs 18.9%). The largest relative increases were in the malpresentation group (10.8% vs 16%) and previous caesarean section (4.5% vs 15.2%).

CONCLUSIONS

These results suggest that there has been a lowering in the overall threshold concerning the decision to carry out a caesarean section rather than changes in obstetric management. Obstetricians and the women in their care have to decide whether the current balance between risk and benefit is acceptable or whether they wish to alter the underlying philosophy if any significant reduction is to be sustained.

Postpartum fecal incontinence is more common in women with irritable bowel syndrome

PURPOSE

Anal sphincter damage can occur during vaginal delivery and may lead to impairment of fecal continence. The aim of this study was to determine the influence of irritable bowel syndrome on symptoms of fecal incontinence following first vaginal delivery.

METHODS

A prospective, observational study was performed before delivery, six weeks, and six months following delivery in primiparous women. A bowel function questionnaire was completed, and anal vector manometry, mucosal electrosensitivity, pudendal nerve terminal motor latency, and anal endosonography were performed. A total of 208 women were assessed before and after delivery, and 104 primigravid women were studied after delivery only. A total of 34 of 312 (11 percent) had an existing diagnosis of irritable bowel syndrome.

RESULTS

The prevalence of abnormal manometry or endosonography was similar in women with and without irritable bowel syndrome. However, six weeks after delivery, women with irritable bowel syndrome had a higher incidence of defecatory urgency (64 percent) and loss of control of flatus (35 percent) compared with those without (urgency, 10 percent, P < 0.001; flatus, 13 percent, P = 0.007). The incidence of frank fecal incontinence was similar in the two groups. Women with IBS had increased mucosal sensitivity to electrical stimulation of the upper anal canal both before and after delivery.

CONCLUSION

Women with IBS are more likely to experience subjective alteration of fecal continence postpartum compared with the healthy primigravid population, but they are not at increased risk of anal sphincter injury.