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Toward normal birth–but at what cost?
American Journal of Obstetrics and Gynecology, Volume 215, Issue 4, October 2016, Pages 439 - 444
The rate of cesarean delivery has become an important health care issue, and has attracted the attention of governments, professional organizations, health care administrators, clinicians, and patients. This has resulted in the generation of guidelines, clinical recommendations, and other documents aimed at increasing the likelihood of vaginal delivery. Sometimes, these recommendations are formulated with limited input from clinicians. In some countries, such as the United Kingdom, external pressure exerted on clinicians to reduce the rate of cesarean delivery has been the subject of public debate, and has led to unintended consequences, including an increase in medicolegal tensions. In the United States and Australia, recent recommendations generated by professional bodies have advocated that clinicians should change practice to reduce the rate of cesarean delivery. We do not summarize the risks and benefits of cesarean birth in different clinical situations, which have been the subject of numerous reviews. Rather, we try to examine the potential implications of such policies in light of recent observations made in maternity units, judicial decisions, and clinical research. The emphasis is on maternal morbidity and patient autonomy. This may include the negative consequences of increasingly risky attempts at vaginal birth after cesarean delivery such as uterine rupture, higher rates of pelvic floor and anal sphincter trauma due to rising forceps rates, and a bias against elective cesarean delivery on maternal request.
Key words: birth, birth trauma, cesarean delivery, guidelines, pelvic floor, policy directives.
The rate of cesarean delivery (CD) has been rising, seemingly inexorably, across the Western world as well as in developing countries. This trend is clear in the United States,1 United Kingdom,2 and Australia,3 although there is some evidence that CD rates have plateaued in the last 5 years.3 In the United States, CD has become the commonest surgical procedure.1
In the United Kingdom and Australia, policymakers have been particularly active in trying to reduce CD rates. The results are guidelines, eg, those issued by the National Institute for Health and Care Excellence (NICE) in the United Kingdom4 and policy directives such as “Towards Normal Birth” in New South Wales.5 The American Congress of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine6 have recently published documents that promote forceps and encourage a permissive approach to longer second stages as a means of reducing CD rates, and the Clinical Excellence Commission in New South Wales has issued recommendations that are likely to result in higher forceps rates.7 At times, the involvement of obstetricians in the production of such documents has been nominal.8
There likely are multiple factors driving the increase in CD rates internationally, and across very different health care delivery systems. However, several predictors of CD can consistently be identified: a reduction in multiparity in the obstetric population, an increase in maternal age at first delivery, and the obesity epidemic and associated increases in medical morbidity such as gestational diabetes.9 The obesity epidemic has multiple consequences, none of them favorable to maternal and perinatal health.10 and 11
In the United States, changes in reimbursement levels, medicolegal concerns, and patient choice in favor of a delivery mode that provides greater control over timing and reduces the risk of pelvic floor damage also seem to contribute.12
Demographic factors are strong predictors of cesarean birth in the developed world and at least partly explain the rise in CD rates. In fact, it seems remarkable that perinatal3 and maternal13 mortality indicators are still trending downward despite these substantial demographic shifts toward ever-increasing numbers of pregnancies at high risk of complications.
Policymakers strive to reduce the number of cesarean births to limit immediate costs, since maternity services take an ever-larger share of health budgets. In addition to administrators and government officials being anxious about the increasing use of scarce health care resources, there is a strong movement that believes that obstetricians are primarily responsible (indeed, to blame) for the rise in intervention rates. As a result there is pressure on services and individuals to change clinical practice. The CD rate has become a primary key performance indicator of obstetric services, and this at a time when it is becoming increasingly clear that even solid obstetric morbidity measures such as postpartum hemorrhage, peripartum infection, severe perineal laceration, neonatal morbidity, and venous thromboembolism are of limited use as key performance indicators, even with optimal data collection.14
The results of this development are increasingly becoming visible. Much can be learned from the experience in the United Kingdom where the National Health Service (NHS) has exerted considerable micromanagement of clinical practice for over a decade. We have selected 2 areas in which the pressure on clinicians to reduce CD rates is particularly likely to place mothers and babies in danger:
Increasing emphasis on vaginal birth after CD
One of the few options available for lowering CD rates is to increase vaginal birth after CD (VBAC) and utilization has fluctuated widely in the United States. In the United Kingdom and Australia, VBAC or trial of labor after cesarean has not always been well received by patients, and this has resulted in the establishment of dedicated clinics designed to promote trials of labor in patients with previous CD, and the increased use of labor augmentation under these circumstances. It appears that pressure on CD rates is leading to increasingly risky VBAC attempts: historical complication data may no longer be applicable to current practice. And even data obtained under conservative criteria show increased risks for mother and child compared to elective CD.15 The risks of VBAC are considerably diminished if the woman has had a previous vaginal delivery but <20% are in that situation.16 In a large Canadian study, of 28,406 women with no prior vaginal deliveries, 7614 planned a vaginal birth but only 3297 delivered vaginally. The risk of life-threatening outcomes was significantly increased in those who planned a vaginal birth.16 In a recent study conducted in a VBAC clinic at St George's Hospital in Sydney,17 567 women with previous CD were included, of whom 396 were deemed VBAC candidates; 226 (40%) agreed to VBAC, of whom 160 (28%) had a trial of labor. This resulted in 75 normal vaginal deliveries, 28 instrumental deliveries, and 57 emergency CD, which implies that 13% of all women with prior CD eventually delivered normally, and 18% via the vaginal route. There were 2 perinatal deaths: 1 from a stillbirth at 40+6 weeks, another from a uterine rupture while receiving oxytocin stimulation. There was another uterine rupture that was survived by mother and child. On an intention-to-treat basis these figures translate to a perinatal mortality of 1:113.17 While this may be described as anecdotal evidence, it provides data on contemporaneous practice under increasing pressure to enhance VBAC uptake.
Increasing forceps rates
Forceps use has been decreasing all over the developed world, with the great majority of vaginal operative deliveries in continental Europe, Scandinavia, and North America now being done by vacuum. In 1989, Chalmers and Chalmers18 declared that the “obstetric vacuum extractor is the instrument of choice for operative vaginal delivery.” In the United States and Germany, forceps rates have now dropped to <1%.19 and 20
Forceps use is rare in Scandinavia and Italy, and there has been no forceps use in Denmark for over 10 years. Curiously, this trend is being reversed in some jurisdictions. In England, forceps rates have doubled since 2004, from 3.3–6.8%,21 and this development is also evident in Australia. In addition, there seems to be a trend toward increasingly difficult and rotational forceps use in an attempt to avoid CD.22 and 23 In the United States, recent ACOG statements seem to encourage a greater use of forceps to avoid CD.24
It has been known for many years that forceps can be traumatic to the fetus.25 However, this concern is balanced by the risk of cephalhematoma in vacuum birth,26 and the relative advantages and disadvantages of forceps and vacuum as regards the newborn is a complex subject outside the scope of this piece.
The situation as regards the mother is much clearer. Encouraging the use of forceps is worrisome, given recent evidence linking this type of operative vaginal delivery with pelvic floor trauma. Forceps use is well established as the major risk factor for both anal sphincter and levator trauma or “avulsion.”27 Avulsion in particular is not yet generally recognized as a major form of obstetric trauma due to the fact that it is usually occult. In simple terms, the levator ani is disconnected or peeled off its insertion on the os pubis at crowning. Due to the greater elasticity of the vagina itself, the tear remains invisible behind intact vaginal skin, although it is occasionally exposed by a large lateral vaginal tear.28 Once peripartum changes have settled down, avulsion is palpable,29 and 30 although the diagnostic gold standard is tomographic ultrasound.31 It has recently become clear that such tears are the missing link between vaginal childbirth and prolapse, especially of the bladder and uterus.32 and 33 In the presence of avulsion, prolapse is much more likely to recur.34
This specific form of pelvic trauma was forgotten only to recently be rediscovered almost 70 years after its first description by De Lee35 in 1938. A recent direct comparison between 2 Sydney teaching hospitals showed marked differences in trauma rates, explained almost entirely by variations in forceps utilization.36 Odds ratios for levator avulsion with forceps relative to vacuum are between 3.4–11.4,27 and sphincter trauma is also much more common with forceps, with an odds ratio of 1.83 (1.66–2.03) in a recently completed metaanalysis (63 studies, n = 546,796 forceps, n = 1,397,193 vacuum) (unpublished data).
On the basis of our own modeling37 we have calculated that doubling the forceps rates in the United Kingdom between 2004 and 2014 may now have resulted in over 100,000 additional major levator and anal sphincter tears. The same modeling suggests that women in the United Kingdom now are exposed to a 30–40% higher risk of such major tears compared to women delivering in the United States or Germany–and this is without considering the effects of rotational forceps. This is likely to cause substantial future morbidity: anal sphincter tears are the primary modifiable risk factor for anal incontinence in women,38 and levator trauma is associated with both pelvic organ prolapse32 and 33 and prolapse recurrence after surgical correction.34 This is not surprising since avulsion substantially enlarges the levator hiatus, the largest potential hernial portal in the human body. In addition, traumatic childbirth may result in substantial psychological trauma,39 which may be exacerbated by constant reminders provided by symptoms of pelvic floor dysfunction such as urinary and fecal incontinence, dyspareunia, vaginal laxity, and symptoms of prolapse.
On the basis of current data it seems impossible to predict the effect of different forms of obstetric management on pelvic floor morbidity decades into the future. However, a recent Danish study on the lifetime risk of prolapse surgery since the late 1970s provides a fascinating glimpse.40 Lowenstein et al describe a substantial reduction in the lifetime risk for prolapse surgery in Denmark from the late 1970s through 2008, from 26.9-18.7%, ie, about 30%. Given that forceps use declined in Denmark from the late 1960s onward, and that it has been rarely used over the last 25 years,41 and given a mean latency between a traumatic first birth and presentation for prolapse surgery of >30 years,42 it seems reasonable to hypothesize that this reduction in prolapse surgery may be at least partly due to the substitution of forceps by (less traumatic) vacuum deliveries. These observations are consistent with recent epidemiological data from 2 large prospective studies conducted in the United Kingdom and Scandinavia. The Swedish Pregnancy, Obesity and Pelvic Floor Study43 showed a strong link between vaginal birth and symptomatic prolapse 20 years postpartum, while the Prolapse and Incontinence Long-term Research Study44 confirmed a reduced risk of objectively measured signs of pelvic organ prolapse 12 years after cesarean delivery compared to vaginal birth, with forceps a major risk factor.
Bias against CD on maternal request
The passion of some against CD upon maternal request seems to have gone far. There are reports of women compelled to have a psychiatric assessment after making this choice. Indeed, the current version of NICE guidelines45 regarding CD states that, “Interventions that may be appropriate include: …referral to a psychologist or a mental health professional.” In some cases this has resulted in what may be described as harassment and intimidation of individuals and referrals to psychiatric services. Even if well intentioned, such policies would serve to discourage women from making such a request and may stigmatize them. This is at a time when the more we know about maternal trauma in childbirth, the more reasonable this supposedly pathological fear of childbirth or tocophobia appears to the unbiased observer. To dismiss such fears as pathological disempowers women who may at times be better informed than their caregivers, due to the increasing ease with which up-to-date information on risks and benefits of elective CD are accessible on the Internet. Arguments in favor of denying such requests are based either on ignorance of those benefits (“it’s better for you and your baby to try for a normal delivery”) or on claims of resource restriction (“our public health system can’t afford it”). The latter is as invalid as the first, given that NICE demonstrated an excess cost of elective CD of only $122 per case,45 and this while completely omitting any consideration of maternal birth trauma. Recently, a prominent author and women’s health journalist claimed that in this matter “birth ideology battles against scientific advancement and female autonomy,”46 and the authors concur.
Some women who have been dissuaded from CD upon request may eventually have a traumatic vaginal delivery, with permanent damage to the anal sphincter and levator. This can lead to long-term morbidity such as anal incontinence and pelvic organ prolapse. It is anticipated that urogynecologists and investigators focusing on pelvic floor injury would be asked to comment as malpractice litigation emerges from denying patients their choice. Indeed, anyone denying a CD upon maternal request takes an implicit calculated risk, not only for their patient, but also for themselves, professionally, and the institutions they represent. There is also the moral and ethical issue of patient autonomy.
However, pressure on clinicians to avoid CD may at times result in even more serious outcomes that are obvious not just to the expert witness, but to families and society at large. An independent investigation into events at Furness General Hospital (now part of Morecambe Bay NHS Foundation Trust) in England was published in March 201547 and may serve as an example of a cultural change in the provision of obstetric services which, in the opinion of the authors, is increasingly affecting obstetrics worldwide.
Why are we so obsessed with the CD rate?
One has to ask what has prompted obstetricians and midwives to develop such a single-minded focus on avoiding medical intervention, especially CD. On the one hand, economic factors and concern about increasing numbers of difficult and potentially dangerous repeat CD are clearly justified. On the other hand it seems preposterous to judge the quality of maternity care on the basis of one single indicator when this is clearly impossible to do even with sophisticated analyses of perinatal morbidity.14
Risks and benefits need to be discussed rationally on a case-by-case basis, but any such discussion needs to include a consideration of obstetric trauma, especially levator and sphincter tears. This should not be too difficult once obstetricians acknowledge that such trauma is much more common than claimed in their textbooks. Providing patients with balanced information on risks and benefits is what we are supposed to do for gynecological patients, every day of our lives.
However, other influences are at work, sometimes through ill-advised public pressure, sometimes through government officials and administrators, but sometimes through poorly designed professional guidelines. Administrators, after all, will frequently rely on professional expert voices. A recent article in the American Journal of Obstetrics and Gynecology comprehensively chronicled how easy it is for largely faceless professional committees to produce guidelines that are unlikely to be helpful.48 ACOG has recently published a Committee Opinion that explicitly dismisses obstetric trauma as a performance indicator of obstetric services. The justification for this stance was that a focus on maternal trauma would likely lead to further increases in the CD rate. To quote, “The rate of severe perineal lacerations should not be used as a measure of obstetric quality,” one of the three reasons being that ‘diminishing the use of operative vaginal delivery,’ in an effort to decrease severe perineal lacerations, likely would result in an increased rate of CD.” Clearly, the committee regarded the CD rate a more important performance indicator than obstetric trauma–and this while omitting to mention major pelvic floor trauma altogether.49 We disagree with this recommendation.50
An obsession with CD rates, regardless of whether it is motivated by rational concerns or ideology, clearly has the potential to do harm. In the United Kingdom, this harm is becoming increasingly evident to the public, and medicolegally relevant. The Morecambe Bay report47 exposed systemic problems in an NHS hospital that resulted in avoidable harm to mothers and babies, including tragic and unnecessary deaths, and it is highly relevant to our topic. Here are a few quotes from the Morecambe Bay report47: “There were a group of midwives who thought that normal childbirth was the… be all and end all… at any cost… yeah, it does sound awful, but I think it’s true – you have a normal delivery at any cost.” Another interviewee “…was aware that there were certain midwives that would push past boundaries.” A third said, “…a couple of senior people who believed that in all sincerity they were processing the agenda as dictated at the time… to uphold normality… there’ve been 1 or 2 influential figures who’ve perpetrated that… sort of approach and… there’s nobody challenging….”
Unfortunately, the nationwide review of NHS Maternity Services triggered by the Morecambe Bay report,47 “Better births: improving outcomes of maternity services in England,”51 is likely to make matters worse rather than better. While the former chronicled the consequences of delayed or absent intervention, the latter advocates less intervention; and while the former identified excessive autonomy of midwives as a root cause of disaster, the latter report argues for more of the same. This report is unlikey to be the last word in this matter.
Concerns regarding ever-increasing CD rates are understandable and justified. The risks of CD–especially repeat procedures–have been pointed out many times, which is why we will not do so here. However, it is entirely inappropriate to use CD rates as a key performance indicator for the quality of an obstetric service52 and 53 without considering maternal and perinatal morbidity and mortality. Lower-than-expected, risk-adjusted CD rates have been found to be associated with higher-than-expected adverse maternal or neonatal outcomes.53 The dangers of not performing a CD sometimes outweigh the risks of doing so. Ignoring such (immediate and long-term) dangers is likely to have substantial unintended negative consequences. Guidelines and policy directives are not an excuse to ignore one’s clinical judgment, ethical precepts, research findings, or the law of the land.54
At any rate, the final decision has to be the patient's. A recent Supreme Court decision in the United Kingdom is likely to influence the practice of antenatal and intrapartum consent, and not just in Europe. The decision in the case Montgomery v Lanarkshire Health Board (Supreme Court of the United Kingdom 11 )55 states: “It is impossible to consider a particular procedure in isolation from its alternatives. Pregnancy is a powerful illustration. Where either mother or child is at heightened risk from vaginal delivery, doctors should volunteer the pros and cons of that option compared to a cesarean.” The court defines planned natural birth as a “procedure” or “treatment,” which implies a much greater duty to obtain informed consent than previously. In essence, we will have to treat pregnant women just like our gynecological patients. From now on, guidelines or policy directives may no longer protect practitioners. The Bolam test is history: it is no longer sufficient to show that one has fulfilled the standards of a responsible body of medical opinion.56
Prior to a gynecological procedure, we have to inform patients of complications that may occur at a rate of as low as 1:1000, but in the antenatal clinic and labor ward it is not common practice to inform a 38-year-old nullipara of the inescapable fact that the likelihood of emergency operative delivery in her case is >50%, and that, even with spontaneous vaginal delivery, the risk of a levator tear is approximately 20%, and that of an anal sphincter tear about 15%. Would many women choose VBAC if they were informed of a local success rate of <35%, and a perinatal mortality rate of almost 1:100, or even 1:300? It's almost beside the point to mention the increased risk of major obstetric trauma with VBAC in such patients.
Women who come to us for antenatal and intrapartum care deserve to be treated like adults. They have a right to up-to-date, unbiased, and accurate information. This includes information on the risks of natural birth, including maternal obstetric trauma, and such information has to be provided by those trained to obtain informed consent. The interests of government officials, administrators, and pressure groups in lowering the CD rate are equally irrelevant from medical, ethical, and legal perspectives. Clinicians are well advised to ignore such pressure. Failing to do so exposes patients to a higher likelihood of negative outcomes, and obstetricians to increasingly substantial medicolegal risk.
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