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NIH Consensus Development Conference Statement on
Vaginal Birth After Cesarean: New Insights
NIH Consensus and State-of-the-Science Statements
Volume 27, Number 3
March 810, 2010
NATIONAL INSTITUTES OF HEALTHOice o the Director
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About the NIH Consensus Development Program
National Institutes o Health (NIH) Consensus and State-o-the-Science Statements are prepared by independent panels o health
proessionals and public representatives on the basis o (1) the resultso a systematic literature review prepared under contract with theAgency or Healthcare Research and Quality (AHRQ), (2) presentationsby investigators working in areas relevant to the conerence questionsduring a 2-day public session, (3) questions and statements romconerence attendees during open discussion periods that are part othe public session, and (4) closed deliberations by the panel duringthe remainder o the second day and the morning o the third. Thisstatement is an independent report o the panel and is not a policystatement o the NIH or the Federal Government.
The statement reects the panels assessment o medical knowledgeavailable at the time the statement was written. Thus, it provides asnapshot in time o the state o knowledge on the conerence topic.When reading the statement, keep in mind that new knowledge isinevitably accumulating through medical research, and that the inormationprovided is not a substitute or proessional medical care or advice.
Reerence Inormation
Individuals who wish to cite this statement should use theollowing ormat:
Cunningham FG, Bangdiwala S, Brown SS, Dean TM, Frederiksen M, Rowland Hogue CJ, King T, Spencer Lukacz E, McCullough LB,Nicholson W, Petit N, Probstfeld JL, Viguera AC, Wong CA, ZimmetSC. National Institutes o Health Consensus Development ConerenceStatement: Vaginal Birth Ater Cesarean: New Insights. March 810,2010. Obstetrics & Gynecology. 2010; 115(6):12791295.
Publications Ordering Information
NIH Consensus Statements, State-o-the-Science Statements, andrelated materials are available by visiting http://consensus.nih.gov; bycalling toll ree 8886442667; or by emailing [email protected] requests can be mailed to the NIH Consensus DevelopmentProgram Inormation Center, P.O. Box 2577, Kensington, MD 20891.When ordering copies o this statement, please reerence item number
2010-00122-STMT.
The evidence report prepared or this conerence through AHRQ isavailable on the web via http://www.ahrq.gov/clinic/tp/vbacuptp.htm.Printed copies may be ordered rom the AHRQ PublicationsClearinghouse by calling 8003589295. Requesters should askor AHRQ Publication No. 10-E003.
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NIH Consensus Development Conference Statement on
Vaginal Birth After Cesarean: New Insights
NIH Consensus and State-of-the-Science Statements
Volume 27, Number 3
March 810, 2010
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Disclosure Statement
All o the panelists who participated in this conerence
and contributed to the writing o this statement were
identifed as having no fnancial or scientifc conict o
interest, and all signed orms attesting to this act. Unlike
the expert speakers who present scientifc data at the
conerence, the individuals invited to participate on NIH
Consensus and State-o-the-Science Panels are reviewed
prior to selection to ensure that they are not proponents
o an advocacy position with regard to the topic and are
not identifed with research that could be used to answer
the conerence questions.
For more inormation about conerence procedures,
please see http://consensus.nih.gov/aboutcdp.htm.
Archived Conference Webcast
The NIH Consensus Development Conerence on
Vaginal Birth Ater Cesarean: New Insights waswebcast live March 810, 2010. The webcast is
archived and available or viewing ree o charge at
http://consensus.nih.gov/2010/vbac.htm.
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Abstract
Objective
To provide healthcare providers, patients, and the
general public with a responsible assessment o currently
available data on vaginal birth ater cesarean (VBAC).
Participants
A non-Department o Health and Human Services,
nonadvocate 15-member panel representing the
felds o obstetrics and gynecology, urogynecology,
maternal and etal medicine, pediatrics, midwiery,
clinical pharmacology, medical ethics, internal medicine,
amily medicine, perinatal and reproductive psychiatry,
anesthesiology, nursing, biostatistics, epidemiology,
healthcare regulation, risk management, and a public
representative. In addition, 20 experts rom pertinent felds
presented data to the panel and conerence audience.
Evidence
Presentations by experts and a systematic review o
the literature prepared by the Oregon Evidence-based
Practice Center, through the Agency or Healthcare
Research and Quality (AHRQ). Scientifc evidence was
given precedence over anecdotal experience.
Conference Process
The panel drated its statement based on scientifc
evidence presented in open orum and on published
scientifc literature. The drat statement was presented
on the fnal day o the conerence and circulated to the
audience or comment. The panel released a revised
statement later that day at http://consensus.nih.gov. Thisstatement is an independent report o the panel and is
not a policy statement o the National Institutes o Health
(NIH) or the Federal Government.
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Conclusions
Given the available evidence, trial o labor is a reasonable
option or many pregnant women with one prior low
transverse uterine incision. The data reviewed in this
report show that both trial o labor and elective repeat
cesarean delivery or a pregnant woman with one prior
transverse uterine incision have important risks and
benefts and that these risks and benefts dier or the
woman and her etus. This poses a proound ethical
dilemma or the woman, as well as her caregivers,
because beneft or the woman may come at the price
o increased risk or the etus and vice versa. This
conundrum is worsened by the general paucity o high-
level evidence about both medical and nonmedical
actors, which prevents the precise quantifcation o
risks and benefts that might help to make an inormed
decision about trial o labor compared with elective
repeat cesarean delivery. The panel was mindul o these
clinical and ethical uncertainties in making the ollowingconclusions and recommendations.
One o the panels major goals is to support pregnant
women with one prior transverse uterine incision to make
inormed decisions about trial o labor compared with
elective repeat cesarean delivery. The panel recommends
that clinicians and other maternity care providers use
the responses to the six questions, especially questions
3 and 4, to incorporate an evidence-based approachinto the decisionmaking process. Inormation, including
risk assessment, should be shared with the woman at
a level and pace that she can understand. When trial o
labor and elective repeat cesarean delivery are medically
equivalent options, a shared decisionmaking process
should be adopted and, whenever possible, the womans
preerence should be honored.
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The panel is concerned about the barriers that women
ace in gaining access to clinicians and acilities that
are able and willing to oer trial o labor. Given the low
level o evidence or the requirement or immediatelyavailable surgical and anesthesia personnel in current
guidelines, the panel recommends that the American
College o Obstetricians and Gynecologists and the
American Society o Anesthesiologists reassess this
requirement with specifc reerence to other obstetric
complications o comparable risk, risk stratifcation,
and in light o limited physician and nursing resources.
Healthcare organizations, physicians, and otherclinicians should consider making public their trial o
labor policies and VBAC rates, as well as their plans
or responding to obstetric emergencies. The panel
recommends that hospitals, maternity care providers,
healthcare and proessional liability insurers, consumers,
and policymakers collaborate on the development o
integrated services that could mitigate or even eliminate
current barriers to trial o labor.
The panel is concerned that medical-legal considerations
add to, and in many instances exacerbate, these
barriers to trial o labor. Policymakers, providers, and
other stakeholders must collaborate in developing and
implementing appropriate strategies to mitigate the
chilling eect the medical-legal environment has on
access to care.High-quality research is needed in many areas. The panel
has identifed areas that need attention in response to
question 6. Research in these areas should be given
appropriate priority and should be adequately unded
especially studies that would help to characterize more
precisely the short-term and long-term maternal, etal,
and neonatal outcomes o trial o labor and elective repeat
cesarean delivery.
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Introduction
Vaginal birth ater cesarean (VBAC) describes vaginal
delivery by a woman who has had a previous cesarean
delivery. For most o the 20th century, once a woman
had undergone a cesarean delivery, clinicians believed
that her uture pregnancies required cesarean delivery.
Studies rom the 1960s suggested that this practice may
not always be necessary. In 1980, a National Institutes
o Health (NIH) Consensus Development Conerence
Panel questioned the necessity o routine repeat cesarean
deliveries and outlined situations in which VBAC couldbe considered. The option or a woman with a previous
cesarean delivery to have a trial o labor was oered and
exercised more oten in the 1980s through 1996. Since
1996, however, the number o VBACs has declined,
contributing to the overall increase in cesarean delivery
(Figure 1). Although we recognize that primary cesarean
deliveries are the driving orce behind the total cesarean
delivery rates, the ocus o this report is on trial o laborandrepeatcesarean deliveries.
Figure 1. Rates of Total Cesarean Deliveries, Primary
Cesarean Deliveries, and VBAC, 19892007
VBAC
1989
0
5
10
15
20
25
30
35
1991 1993 1995 1997 1999 2001 2003 2005 2007
Total cesarean delivery
Primary cesarean delivery
Year
Rateper100livebirths
Data rom the National Center or Health Statistics.
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A number o medical and nonmedical actors have
contributed to this decline in the VBAC rate since the
mid-1990s, although many o these actors are not well
understood. A signifcant medical actor that is requentlycited as a reason to avoid trial o labor is concern about
the possibility o uterine rupturebecause an unsuccessul
trial o labor, in which a woman undergoes a repeat
cesarean delivery instead o a vaginal delivery, has a
a higher rate o complications compared to VBAC or
elective repeat cesarean delivery. Nonmedical actors
include, among other things, restrictions on access to a
trial o labor and the eect o the current medical-legalclimate on relevant practice patterns. To advance
understanding o these important issues, the Eunice
Kennedy ShriverNational Institute o Child Health and
Human Development and the Ofce o Medical Applications
o Research o NIH convened a Consensus Development
Conerence on March 810, 2010. The conerence was
grounded in the view that a thorough evaluation o the
relevant research would help pregnant women and theirmaternity care providers when making decisions about
the mode o delivery ater a previous cesarean delivery.
Improved understanding o the clinical risks and benefts
and how they interact with nonmedical actors also may
have important implications or inormed decisionmaking
and health services planning.
The ollowing key questions were addressed by theConsensus Development Conerence:
1. What are the rates and patterns o utilization o trial
o labor ater prior cesarean delivery, vaginal birth
ater cesarean delivery, and repeat cesarean delivery
in the United States?
2. Among women who attempt a trial o labor ater
prior cesarean delivery, what is the vaginal deliveryrate and the actors that inuence it?
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3. What are the short- and long-term benefts and harms
to the mother o attempting trial o labor ater prior
cesarean versus elective repeat cesarean delivery,
and what actors inuence benefts and harms?4. What are the short- and long-term benefts and
harms to the baby o maternal attempt at trial o
labor ater prior cesarean versus elective repeat
cesarean delivery, and what actors inuence
benefts and harms?
5. What are the nonmedical actors that inuence the
patterns and utilization o trial o labor ater priorcesarean delivery?
6. What are the critical gaps in the evidence
or decisionmaking, and what are the priority
investigations needed to address these gaps?
Invited experts presented inormation pertinent to the
posed questions and a systematic literature review
prepared under contract with AHRQ, available athttp://www.ahrq.gov/clinic/tp/vbacuptp.htm, was
summarized. Conerence attendees asked questions
and provided comments. Ater weighing the scientifc
evidence, an unbiased, independent panel prepared
this consensus statement.
Pregnant women, clinicians, and investigators use
terms in conicting and conusing ways. For consistencythroughout this document, the ollowing defnitions
are provided:
Trial o labor: A planned attempt to labor by a womanwho has had a previous cesarean delivery, also known
as trial o labor ater cesarean.
Vaginal birth ater cesarean delivery (VBAC): Vaginaldelivery ater a trial o labor; that is, a successul trialo labor.
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1. What Are the Rates and Patterns oUtilization o Trial o Labor Ater PriorCesarean, Vaginal Birth Ater Cesarean,and Repeat Cesarean Delivery in theUnited States?
The overall cesarean delivery rate is the sum o primary and
repeat cesarean deliveries per 100 live births. Following
a decline between 1990 and 1996, cesarean delivery
rates in the United States rose markedly rom 21 percent
in 1996 to 32 percent in 2007 (see Figure 1). Both the
primary and repeat cesarean birth rates have risen. Among
women with a prior cesarean delivery, VBAC rates vary
by racial/ethnic status, medical condition, region o the
country, type and location o hospital, and may vary by
type o provider. For Medicaid patients, VBAC rates
are higher or women enrolled in health maintenance
organizations or who deliver at public (not private) hospitals.
Various surveys have revealed that since 1996, approximately
one-third o hospitals and one-hal o physicians no
longer oer trial o labor. A survey o American College
o Obstetricians and Gynecologists Fellows showed that,
between 2003 and 2006, 26 percent stopped oering
a trial o labor or women with a history o cesarean
deliveries regardless o prior vaginal delivery experience.
A woman is at low risk or pregnancy complications i
she has completed 37 weeks o gestation with one etuswhose head is in the vertex position in the womb and has
no obstetric or medical complications. Among low-risk
women, the repeat cesarean delivery rate had increased
to 89 percent by 2003. Since 2003, U.S. Standard Birth
Certifcates have included inormation on VBAC and
trial o labor. Among the 19 states that had adopted
the standard certifcate, approximately 92 percent o
all women who had a previous cesarean had a repeatcesarean or their next delivery in 2006. A sharp rise in
repeat cesareans was observed at all maternal ages
and or all racial/ethnic groups.
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Given these trends, VBAC is an important issue to explore.
Although the number o women and their maternity care
providers aced with the question o whether to attempt
trial o labor has markedly increased, there has been aconcurrent, dramatic drop in VBAC. Yet cesarean and
VBAC rates are identifed as quality indicators or maternal
health by policymakers, insurance providers, and healthcare
quality monitoring groups. Success o trial o labor is
consistently high, ranging rom 60 to 80 percent, whereas
the risk o uterine rupture is low, at less than 1 percent.
Regardless, one reason given or reduced VBAC is
concern about uterine rupture during trial o labor.
Little is known about population-based rates and patterns
o utilization o trial o labor ater previous cesarean
deliveries. A potential source o inormation about this issue
is the Pregnancy Risk Assessment Monitoring System
(PRAMS), an ongoing surveillance program conducted by
the Centers or Disease Control and Prevention and state
health departments. PRAMS is a population-based survey
o a sample o women who have recently delivered. Each
year, a relatively small sample o postpartum women is
selected in each state (n=1,300 to n=3,400). In addition
to a core questionnaire, participating states may choose
to supplement rom a set o standard questions or derive
questions o their own.
New Jersey represents a good example o the use o
birth data. New Jersey tracked trial o labor and repeatcesareans rom 1997 to 2008 using electronic birth systems.
Over this time period, there has been an increase in repeat
cesarean deliveries rom less than 50 percent to nearly
85 percent. There was very little dierence in this rate
between women with or without private insurance or by
maternal risk status. Between 2003 and 2005, 79 percent
o low-risk women in New Jersey underwent repeat
cesarean delivery without a trial o labor. Since 2009,New Jersey has been utilizing PRAMS to learn more
about mothers and providers predelivery intentions
or VBAC and inormed consent or type o delivery.
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In summary, in states where data are collected, VBAC
has dropped dramatically since 1996. Although the
data among racial/ethnic groups vary, repeat cesarean
deliveries without trial o labor have increased in all thesegroups. Rates o repeat cesarean continue to increase
even among women who are low risk.
2. Among Women Who Attempt a Trial oLabor Ater Prior Cesarean, What Is the
Vaginal Delivery Rate and the FactorsThat Inuence It?
Although the trial o labor rate has declined dramatically over
the past several decades, the vaginal delivery rate ater trial
o labor has remained constant at approximately 74 percent.
The reported rates are highly variable, the overall strength
o the body o evidence is moderate, and most studies
use data rom large tertiary care and training centers.In addition, many studies are observational and do not
adequately address issues o selection bias. Conounding
and inadequate measurement o variables are a concern.
Taken together, these methodological and statistical
issues limit the strength o the inormation available.
Many demographic and obstetric actors are associated
with the likelihood o VBAC. Race and ethnicity are the
strongest demographic predictors o vaginal delivery ater
trial o labor. Hispanic and Arican American women have
lower rates o VBAC than non-Hispanic white women.
Increasing maternal age, single marital status, and less
than 12 years o education also have been associated
with lower rates o VBAC. Women who deliver at rural and
private hospitals and the presence o maternal disease
(e.g., hypertension, diabetes, asthma, seizures, renal
disease, thyroid disease, heart disease) may also be
associated with a decreased likelihood o VBAC. Greater
maternal height and body mass index below 30 kg/m2
are associated with an increased likelihood o VBAC.
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A prior history o vaginal delivery, either beore or ater a
prior cesarean delivery, is consistently associated with
an increased likelihood o VBAC. For example, in one
retrospective cohort study, the vaginal birth rate ater trialo labor was 63 percent in women with no prior vaginal
delivery, 83 percent in women with a prior vaginal delivery
beore cesarean delivery, and 94 percent in women with
a prior VBAC. The rate o VBAC increases with each prior
VBAC. Nonrecurring indications or cesarean delivery are
also associated with a higher rate o VBAC. For example,
compared to arrest o labor, prior cesarean delivery or
malpresentation is associated with a higher rate o VBAC.Women who previously delivered babies weighing less
than 4,000 grams are more likely to have a VBAC than are
those who delivered heavier babies.
Current pregnancy actors also are associated with vaginal
delivery ater trial o labor, including labor characteristics
and inant actors. Gestational age greater than 40 weeks,
labor augmentation, and labor induction are associated
with a decreased rate o VBAC. The most consistent inant
actor associated with an increased likelihood o VBAC is
birth weight less than 4,000 grams. Lower gestational age
at delivery is associated with increased VBAC rates when
compared to term gestational age at delivery. Labor actors
associated with a higher VBAC rate include greater cervical
dilation at admission or at rupture o membranes. The
likelihood o VBAC increases i cervical eacementreaches 75 to 90 percent. Vertex position, etal head
engagement or a lower station, and higher Bishop score
(a scoring system used to estimate the success o induction
o labor) also increase the likelihood o VBAC. Data
regarding epidural analgesia and VBAC are inconsistent.
A major area o interest is whether antepartum or
intrapartum management strategiesor example, methods
o labor inductioninuence the rate o VBAC. The overallestimated rate o vaginal birth ater any method o labor
induction is 63 percent. Studies demonstrate that the
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rate o VBAC ranges rom 54 percent or induction o
labor with mechanical (transcervical balloon catheter) to
69 percent or induction with pharmacologic methods.
The majority o studies were conducted in large, tertiarycare settings, and many studies were conducted outside
the United States. Results were not stratifed by age,
race, ethnicity, or baseline risk. Rigorous studies have not
compared VBAC rates with dierent induction methods.
Several screening tools have been proposed or
predicting VBAC. These tools take into account actors
such as maternal age, body mass index, prior vaginal
delivery, prior cesarean indication, cervical dilation, and
eacement at admission. The models have reasonable
ability to predict the likelihood o a successul trial o labor
at the population level but are not accurate in predicting
the risk o a uterine rupture or unsuccessul trial o labor.
Studies have not verifed the utility o these screening
tools or predicting outcomes or individual women.
3. What Are the Short- and Long-TermBenefts and Harms to the Mother oAttempting Trial o Labor Ater PriorCesarean Versus Elective RepeatCesarean Delivery, and What Factors
Inuence Benefts and Harms?Overall, pregnancy and birth have inherent risks and
benefts. There is controversy regarding the risks and
benefts o cesarean delivery, and little high-quality
evidence is available about benefts and harms o trial o
labor and elective repeat cesarean delivery specifcally.
A previous NIH State-o-the-Science Conerence
(http://consensus.nih.gov/2006/cesarean.htm) partiallyaddressed the global issues related to benefts and
harms o cesarean compared to vaginal delivery, which
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is out o the scope o this review. Ideally, or the purposes
o counseling women with a prior cesarean delivery about
their options or mode o delivery, data rom women
who gave birth at term should be used. Unortunately,insufcient data are available about women at term only;
thus, this review includes data on outcomes related to
trial o labor compared with elective repeat cesarean
delivery or all women who give birth at all gestational
ages. When data are available or term gestations only,
these data are presented separately.
Limitations to these fndings include diering defnitions
or the outcomes, heterogeneity among studies, and
variation in study designs. Mortality and morbidity o trial
o labor and elective repeat cesarean delivery are likely to
be underestimated due to reporting bias and the potential
or missing complications that occur ater discharge. The
major outcomes reecting benefts and harms o trial o
labor are presented in bold ont and in descending order
o grade o evidence within this section. However, the
actors inuencing these outcomes do not always hold
the same level o evidence, which is highlighted in each
section below.
For women with a prior cesarean delivery, there are
three possible outcomes: a VBAC (i.e., a successul
trial o labor), an unsuccessul trial o labor resulting in
cesarean delivery, or an elective repeat cesarean delivery.
In general, the overallbenefts o trial o labor are directlyrelated to having a VBAC, because these women typically
have the lowest morbidity. Similarly, theharms o trial o
labor are associated with an unsuccessul trial o labor
resulting in cesarean delivery, because these deliveries
have the highest morbidity. Although there is merit in
studying each o these three groups separately, the
data comparing trial o labor to elective repeat cesarean
delivery that were reviewed or this conerence typicallycombined VBAC and unsuccessul trial o labor ending
in cesarean delivery. Consequently, the health outcomes
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reported below or women who have an unsuccessul
trial o labor and subsequently undergo repeat cesarean
delivery are counted in the overall trial o labor cohort(s).
This approach best reects the knowledge that isavailable to women who have had a previous cesarean
delivery at the time they are deciding on the subsequent
mode o delivery or a current pregnancy.
SHORT-TERM BENEFITS FOR TRIAL OF LABOR
High Grade o Evidence
Maternal mortality is low, but it may be increasing in
the United States. Women who have a trial o labor,
regardless o ultimate mode o delivery, are at decreased
risk o maternal mortality compared to elective repeat
cesarean delivery. Although there is some heterogeneity
among studies reporting death in term only compared to
any gestational age, overall estimates o maternal death
number 3.8 per 100,000 or women who undergo a trialo labor compared with 13.4 per 100,000 live births or
elective repeat cesarean delivery (Table 1). At term, these
numbers decrease to 1.9 (trial o labor) compared with
9.6 (elective repeat cesarean delivery) maternal deaths
per 100,000 live births. Studies o actors aecting
maternal mortality with trial o labor and elective repeat
cesarean delivery are o low-grade evidence; however,
they imply lower mortality or trial o labor in high-volumehospitals (more than 500 deliveries per year). Table 1
puts into perspective the death rates o mothers in the
population o women with prior cesarean, relative to other
common causes o death in the general population.
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Table 1. Mortality Rates
Overall
Trial of Labor
Prior CesareanDelivery
Elective Repeat
Cesarean Prior
CesareanDelivery
All-cause mortality in women
by age (per 100,000 total
U.S. population)*
1524 years 42
2534 years 64
3544 years 136Motor vehicle-related
mortality (per 100,000 total
U.S. population)(Men and
women, 2544 years)*
16
Maternal mortality
(pregnancy to delivery,
all ages, per 100,000 live
births)*
13
Maternal mortality in womenwith prior cesarean, all ages,
at delivery, per 100,000 live
births
4 13
* U.S. 2007 National Center or Health Statistics data.
Data rom supporting systematic evidence review.
Moderate Grade o Evidence
The overall risk ohysterectomy is statistically similar ortrial o labor compared with elective repeat cesarean delivery
(157 versus 280 per 100,000, respectively) and may be
less in women at term. Limited evidence suggests that the
risk o hysterectomy increases with induction o labor,
high-risk pregnancy, and increasing number o cesarean
deliveries (420 or one prior cesarean delivery, 900 or
two prior cesarean deliveries, 2,410 or three prior cesarean
deliveries, 3,490 or our prior cesarean deliveries, and8,990 or fve or more prior cesarean deliveries per 100,000).
The risk oblood transusion is not signifcantly dierent
or trial o labor or elective repeat cesarean delivery
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(900 versus 1,200 per 100,000, respectively). Factors that
increase this risk include induction o labor with no prior
vaginal delivery, high-risk pregnancy, and an increased
number o prior cesarean deliveries.
Low Grade o Evidence
There is shorter hospitalization overall or trial o labor
compared to elective repeat cesarean delivery. This
beneft does not pertain to morbidly obese women.
A single study suggests lower rates odeep venous
thrombosis (DVT) in women undergoing trial o labor
compared with elective repeat cesarean delivery
(40 versus 100 per 100,000, respectively).
Insufcient Evidence or Short-Term Beneft
A womans perceptions o her birth experience, initial
parent-inant interactions, and ability to perorm activities o
daily living or initiate breasteeding may dier by mode o
delivery. There are insufcient comparative studies in women
with a prior cesarean delivery to address these issues.
SHORT-TERM HARMS FOR TRIAL OF LABOR
High Grade o Evidence
None
Moderate Grade o Evidence
Uterine rupture is defned as an anatomic separation o
the uterine muscle with or without symptoms. Although
uncommon, this event can be catastrophic and remains
the most dreaded short-term complication o trial o labor.
The concern or uterine rupture is an important actor
aecting counseling regarding risks and benefts o trialo labor. There is a clear increased risk o uterine rupture
in women who have a trial o labor compared to elective
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repeat cesarean delivery. The presence o a uterine
rupture has numerous adverse consequences or both
mother and baby.
Incidence of Uterine Rupture
Considering all gestational ages, uterine rupture occurs
in approximately 325 per 100,000 women undergoing
trial o labor. The risk o uterine rupture or women who
undergo trial o labor at term is 778 per 100,000. The risk
o uterine rupture or women who undergo elective repeat
cesarean delivery is 26 per 100,000 when all gestational
ages are evaluated and 22 per 100,000 or women who
are at term at the time they give birth. Unortunately,
there is no reliable way to predict who will have a uterine
rupture.
Factors That Increase the Risk of Uterine Rupture
The ollowing discussion o actors that aect the risk o
uterine rupture is based on low-grade evidence.
Women with classical and low vertical uterine scars
have an increased risk o rupture when compared to
women who had a low transverse uterine incision at the
time o cesarean delivery. Induction o laborhas been
associated with uterine rupture. However, due to variation
among studies with respect to indications or delivery,
induction protocol, agent and dose, and subsequentuse o oxytocin, it is difcult to identiy an absolute risk
o uterine rupture associated with induction. The risk o
rupture in women at term who have their labor induced
is higher (1,500 per 100,000) than the risk o rupture i
labor starts spontaneously (800 per 100,000). The risk
o rupture may be increased in women who are induced
at more than 40 weeks (3,200 per 100,000 at more than
40 weeks versus 1,500 per 100,000 at 37 to 40 weeks).There does not appear to be an increased risk o rupture
with oxytocin augmentation o spontaneous labor.
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A recently published meta-analysis revealed that an
increase in the number o prior cesarean deliveries
may increase the risks o uterine rupture; two or more
previous cesarean deliveries were associated with higherrupture rates (1,590 per 100,000) than one prior cesarean
delivery (560 per 100,000). Other actors that may
increase the risk o uterine rupture include unavorable
cervical status at the time o admission, obesity, inter-
pregnancy interval o 18 months or less, single-layer
closure or the initial cesarean delivery, an inant weighing
more than 4,000 grams, and giving birth in a low-volume
hospital. Insufcient data are available to quantiy thespecifc eects o these actors.
Factors That Decrease the Risk of Uterine Rupture
Aprior vaginal birth (beore or ater the previous
cesarean delivery) decreases the risk o uterine rupture
to approximately 600 per 100,000.
Consequences of Uterine Rupture
There have been no reported maternal deaths due to
uterine rupture. Overall, 14 to 33 percent o women
will need a hysterectomy when the uterus ruptures.
Approximately 6 percent o uterine ruptures will result in
perinatal death. This is an overall risk o intrapartum etal
death o 20 per 100,000 women undergoing trial o labor.
For term pregnancies, the reported risk o etal death with
uterine rupture is less than 3 percent. Although the risk is
similarly low, there is insufcient evidence to quantiy the
neonatal morbidity directly related to uterine rupture.
Insufcient Evidence or Short-Term Harm
Reported rates oinection vary widely depending on
the defnitions used. Overall, the rates o inection arelow (below 3 percent or less than 3,000 per 100,000)
with increased trends toward higher inection rates with
trial o labor. Morbid obesity, unsuccessul trial o labor,
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and increased number o cesarean deliveries increase
inection rates. Evidence is sparse or rates o short-term
surgical injury. There do not appear to be dierences
between trial o labor and elective repeat cesarean delivery,but surgical injury increases with unsuccessul trial o labor,
vertical abdominal incision (as opposed to Pannenstiel
incision), and increasing number o cesarean deliveries.
LONG-TERM BENEFITS OF TRIAL OF LABOR
High Grade o Evidence
None
Moderate Grade o Evidence
There is an association between cesarean delivery and
abnormal placental position and growth in subsequent
pregnancies and the risk o having abnormal placental
position and growth increases with increasing number o
cesarean deliveries. Although most women in the United
States have two or ewer births, the chance o having
abnormal placental position or growth in subsequent
pregnancy are o great concern or the 28 percent o
women who have more than two births. An important
aspect in counseling women about trial o labor compared
with elective repeat cesarean delivery should thereore
include the womans plans or uture ertility.For the purposes o comparing outcomes between
trial o labor and elective repeat cesarean delivery, it is
recognized that all these women have had at least one
cesarean delivery, and are at baseline higher risk or
abnormal placental position and growth compared to
women who have not had a cesarean delivery. Overall, the
major beneft o trial o labor is the 74 percent likelihood
o VBAC and avoidance o multiple cesarean deliveries.However, women who have an unsuccessul trial o labor
and repeat cesarean delivery do not realize the beneft
o decreased risk or abnormal placental position or
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growth in subsequent pregnancies. The ollowing health
outcomes occur less requently in women who have a
VBAC (i.e., a successul trial o labor) and are o most
concern or women who have more than two births.The incidence oplacenta previa (placenta covering the
cervix) signifcantly increases in women with each additional
cesarean delivery, occurring in 900 per 100,000 women
who have one prior cesarean delivery, 1,700 per 100,000
women who have two prior cesarean deliveries, and
3,000 per 100,000 in women who have three or more
cesarean deliveries. As the number o cesarean deliveries
increase, major morbidity, including placenta accreta
and hysterectomy, also increase when a pleacenta
previa is present.
Even in the absence o placenta previa, the incidence
oplacenta accreta, increta, and percreta (growth
o the placenta into or through the uterine muscle)
increases with the number o cesarean deliveries. This
has a proound eect on the womans uture reproductivecapability. The baseline risk o placenta accreta in a
woman with one prior cesarean delivery is 319 per
100,000; this increases to 570 per 100,000 or two
prior cesarean deliveries, and approximately 2,400 per
100,000 or three or more cesarean deliveries. No actors
have been identifed to decrease this risk. There does
not appear to be an increased incidence oplacental
abruption (i.e., premature separation o the normallyimplanted placenta rom the uterus) with increasing
number o cesarean deliveries, although the risk is
increased when women who have one prior cesarean
delivery are compared to women who have not had a
cesarean delivery.
Low Grade o Evidence
None
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Insufcient Evidence or Long-Term Beneft
Although cesarean delivery has been implicated in other
conditions such as chronic pain, ectopic pregnancy, stillbirth,
and inertility, there are no studies examining these conditions
in women with prior cesarean delivery with respect to trial
o labor compared with elective repeat cesarean delivery.
With respect to complications related to subsequent
surgery, no studies have specifcally compared trial o
labor with elective repeat cesarean delivery. However, it is
generally recognized that an increasing number o abdominal
surgeries is associated with the ollowing complications:
clinically signifcant adhesions, perioperative complications
at time o subsequent repeat cesarean delivery, bowel
and ureteral injuries, and perioperative complications at
time o non-pregnancy-related hysterectomy.
LONG-TERM HARMS OF TRIAL OF LABOR
High or Moderate Grades o EvidenceNone
Low Grade o Evidence
None
Insufcient Evidence or Long-Term Harm
No studies on long-term pelvic foor unction have
compared women who have a trial o labor with women
who have an elective repeat cesarean delivery. Although
women who experience a vaginal delivery may have
increased risks o pelvic oor disorders, such as stress
incontinence or pelvic organ prolapse, compared to
women who have a cesarean delivery, the labor progress
and timing o the original cesarean delivery inuence theserisks. As such, elective repeat cesarean delivery or the
prevention o pelvic oor disorders should not be considered
protective against stress incontinence and prolapse.
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4. What Are the Short- and Long-TermBenefts and Harms to the Baby oMaternal Attempt at Trial o Labor AterPrior Cesarean Versus Elective RepeatCesarean Delivery, and What FactorsInuence Benefts and Harms?
The discussion between women and their maternity care
providers about whether to proceed with elective repeat
cesarean delivery or trial o labor ollowing prior cesarean
delivery must assess potential benefts and harms or bothmother and etus. In contrast to the data on maternal
outcomes, there is little or no evidence on short- or long-
term neonatal outcomes ater trial o labor compared to
elective repeat cesarean delivery. Much o the evidence is
o low quality, characterized by inconsistencies in outcomes
across studies and dierences in outcome defnitions, and
variations in study design. However, there are extensive
data documenting dierences in neonatal outcomesollowing vaginal delivery compared to cesarean delivery in
general. Overall, ollowing cesarean delivery, inants have
increased rates o short-term respiratory sequelae, intererence
with initial mother-inant contact, and delayed breasteeding
initiation compared to inants born vaginally. Long-term
consequences may include asthma. However, there are
little data on these outcomes when trial o labor and
elective repeat cesarean delivery are compared in womenwho had a prior cesarean delivery. Furthermore, there are
essentially no data on actors contributing to neonatal
benefts and harms. The major outcomes reecting benefts
and harms o trial o labor compared to elective repeat
cesarean delivery are presented in bold ont and in
descending order o grade o evidence within this section.
SHORT-TERM OUTCOMES
High Grade o Evidence
None
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Moderate Grade o Evidence
Studies operinatal mortality (death between 20 weeks o
gestation and 28 days o lie) are o moderate quality and
show that the perinatal mortality rate is increased or trial
o labor at 130 per 100,000 compared to elective repeat
cesarean delivery at 50 per 100,000. Although this dierence
is statistically signifcant, the magnitude o the dierence
between the two groups is small and comparable to
the perinatal mortality rate observed among laboring
nulliparous women. The neonatal mortality rate (death in
the frst 28 days o lie) is 110 per 100,000 or trial o labor
compared to 50 per 100,000 or elective repeat cesarean
delivery (Table 2). Table 2 puts into perspective the death
rates o babies in the population o women with prior
cesarean delivery, relative to other causes o death.
Table 2. Mortality Rates per 100,000 Infants
Overall
Trial of LaborPrior Cesarean
Delivery
Elective RepeatCesarean
Delivery PriorCesareanDelivery
All-cause mortality 20
weeks gestation to
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per 100,000. Elective repeat cesarean delivery may have
contributed to the reduction o stillbirths that occur in the
late third trimester and the decline in perinatal mortality
observed over the last two decades, because electiverepeat cesarean delivery is rarely perormed ater 40
weeks, whereas women who undergo trial o labor may
have longer gestations.
Hypoxic ischemic encephalopathy in term inants has
an incidence o 100 per 100,000 live births. That said, it
is considered one o the most catastrophic outcomes and
is one contributor to long-term neurological impairment
in inants. Such neurological damage is one o the most
serious adverse consequences o uterine rupture and a
major reason why women and clinicians are concerned
about electing trial o labor. The systematic evidence
review reported insufcient data on the incidence o
hypoxic ischemic encephalopathy between inants born
ollowing trial o labor compared with elective repeat
cesarean delivery. However, a recent observational study
o more than 33,000 women ound a signifcantly higher
incidence o hypoxic ischemic encephalopathy in trial o
labor compared with elective repeat cesarean delivery (12
cases versus 0 cases, respectively, or 46 per 100,000
or trial o labor compared with 0 per 100,000 or elective
repeat cesarean delivery). Unortunately, the studies on
this important outcome are limited by inconsistency in
study methodology.
Insufcient Evidence
Inants born by elective repeat cesarean delivery may
have higher rates orespiratory sequelae, including
respiratory distress syndrome, transient tachypnea o the
newborn, and need or oxygen and ventilator support
when compared to inants born by VBAC. There is a lack
o data to determine whether substantial dierences in
respiratory outcomes occur in inants born via elective
repeat cesarean delivery compared with inants born
ater trial o labor to women who had a prior cesarean.
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Studies osepsis were o low quality. No meaningul
conclusions could be drawn.
Inants born by elective repeat cesarean delivery are at
increased risk or birth trauma such as etal lacerations.Studies o brachial plexus injury (upper extremity nerve
injury) show an incidence o 180 per 100,000 in inants
born by VBAC compared to 30 per 100,000 among inants
born by elective repeat cesarean delivery. However, there
does not appear to be a substantial dierence in persistent
neurological impairment ater brachial plexus injury between
trial o labor and elective repeat cesarean delivery.
No comparative data exist on breasteeding practices
among women who had a prior cesarean delivery who
undergo trial o labor compared with elective repeat
cesarean delivery.
Comparative data regarding actors aecting mother-
inant bonding, including the long-term well-being o
the inant and early mother-inant contact, are lackingor women undergoing trial o labor or elective repeat
cesarean delivery.
5. What Are the Nonmedical Factors ThatInuence the Patterns and Utilization o
Trial o Labor Ater Prior Cesarean?We considered the inuence o the ollowing nonmedical
actors on practice and utilization patterns related to trial
o labor:
Proessional association practice guidelinesProessional liability concerns among physicians
and hospitalsThe nature and extent o inormed decisionmakingProvider and birth-setting issues
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Health insurance status and insurance reimbursementPatient and provider preerences.The literature syntheses that inormed this consensusconerence did not include these issues as part o the
evidence-based systematic review. Even so, we have
concluded that they are important inuences on access
to trial o labor. We have also concluded that data are
not available to judge therelative impact o these various
actors or how they interact.
Professional Association Practice Guidelines
In 1999, the American College o Obstetricians and
Gynecologists (the College) released a practice guideline
changing its earlier recommendation o encouraging
VBAC to a recommendation that women should be
oered trial o labor i there are no contraindications.
The guideline also stated that trial o labor should be
perormed only in institutions equipped to respondto obstetric emergencies and in settings where
physicians capable o perorming a cesarean delivery
are immediately available to provide emergency care.
According to the College, evidence to support this
guideline was rated as Level C (based on consensus and
expert opinion). Not all institutions were able to comply
with this new standard, which in turn led some to cease
oering trial o labor and thereore VBAC altogether.
Two recent surveys o hospital administrators ound that
30 percent o hospitals stopped providing trial o labor
services because they could not provide immediate surgical
and anesthesia services. Some have reerred to these
policies as VBAC bans. O the hospitals that still oer
trial o labor, more than hal had to change their policies
to comply with the 1999 College recommendation.
A joint statement by the American College o Obstetricians
and Gynecologists and the American Society o
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Anesthesiologists in 2008 also called or the immediate
availability o appropriate acilities and personnel,
including obstetric anesthesia, nursing personnel, and
a physician capable o monitoring labor and perormingcesarean delivery, including an emergency cesarean
delivery, in cases o vaginal birth ater cesarean delivery.
Even so, experts in tracking anesthesia sta resources
have ound that there are too ew anesthesia providers to
ensure immediate anesthesia availability or all hospitals
providing childbirth services. Moreover, they predict that
these shortages will worsen in the uture.
Professional Liability Concerns Among Physiciansand Hospitals
Concerns over liability risk have a major impact on the
willingness o physicians and healthcare institutions
to oer trial o labor. These concerns derive rom the
perception that catastrophic events associated with
trial o labor could lead to compensable claims withlarge verdicts or settlements or etal/maternal injury
regardless o the adequacy o inormed consent. Clearly,
these medical malpractice issues aect practice patterns
among healthcare providers and they played a role in the
genesis o the Colleges 1999 immediately available
guideline.
Members o the American College o Obstetricians andGynecologists confrm that concern over liability is a main
reason they stopped oering trial o labor. A 2009 College
survey revealed that 30 percent o obstetricians stopped
oering trial o labor or perorming VBACs because o
the risk or ear o proessional liability claims or litigation.
This is urther compounded by 29 percent acknowledging
having increased their number o cesarean deliveries and
8 percent having stopped practicing obstetrics altogether.In a recent study o College Fellows, risk o liability
was among the primary reasons cited or perorming a
cesarean delivery.
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In addition, studies have attempted to model the impact
o tort reorm on primary and repeat cesarean delivery
rates and have shown that modest improvements in the
medical-legal climate may result in increases in VBAC andreductions in cesarean deliveries. These analyses suggest
that both caps on noneconomic damages and reductions
in physician malpractice premiums would result in ewer
cesarean deliveries.
The Nature and Extent of Informed Decisionmaking
It is important that women understand the spectrum
o risks and benefts o trial o labor and elective repeat
cesarean delivery, given the evidence that providing such
inormation has a signifcant impact on a womans ability
to make an inormed choice about whether or not trial
o labor is a reasonable option or her. Several studies
suggest thathowrisk is presented and communicated
by providers has a powerul eect on womens decisions.
Along these same lines, the 1999 College guideline urged,Ater thorough counseling that weighs the individual
benefts and risks o VBAC, the ultimate decision to
attempt this procedure or undergo a repeat caesarean
delivery should be made by the woman and her physician.
Presentations at the conerence suggested that this
important recommended practice is not uniormly
ollowed, but there are no strong data documenting
the extent o this shortcoming.Patterns and use o trial o labor also may reect
womens varying levels o knowledge and appreciation
about the benefts and risks o the particular delivery
options available. More generally, there is limited public
understanding o the baseline risks o pregnancy and
childbirth in general.
A variety o decision aids are available to help womenunderstand the risks, benefts, and implications o trial
o labor compared with elective repeat cesarean delivery.
A ew well-designed studies suggest that certain tools
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can increase womens knowledge, reduce their anxiety,
and help them in their decisionmaking process.
Provider and Birth-Setting IssuesNo strong comparative data are available to assess
the relative impact o types o maternity care providers
(obstetrician-gynecologists, amily practice physicians,
midwives) on patterns and utilization o trial o labor ater
controlling or selection bias and patient mix.
Some evidence shows that younger obstetric providers
are less willing and interested in oering trial o labor.This may reect the act that their training occurred at
a time when trial o labor was steadily decreasing.
Women give birth in a variety o settings in and out o
hospitals, including tertiary care centers, community
hospitals, reestanding birth centers, and at home.
Most data on maternal and neonatal outcomes are
collected in tertiary care settings, which means thatthere is little data that assesses these outcomes
across numerous settings. However, there is a positive
association between settings with a high volume o
deliveries and better outcomes, especially lower rates
o neonatal mortality in premature inants.
Health Insurance and Reimbursement
Current data do not allow clear conclusions to be made
about the eect a womans health insurance status has
on her access to trial o labor. It also is not clear whether
overall reimbursement levels or VBAC compared with
elective repeat cesarean delivery have a major inuence
on either hospital or physician practice patterns.
Patient and Provider PreferencesAs a general matter, women report that their preerences
regarding delivery options are inuenced by their
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maternity care providers recommendations and concerns
about saety, including a desire or a healthy baby and
ear o a bad outcome.
Factors linked to womens preerence or pursuing trialo labor include sel-reported desire or their partners
involvement, a sense that labor and vaginal delivery
can be deeply empowering, maternal-inant bonding,
greater ease in breasteeding, and the expectation o an
easier recovery. Conversely, a desire or sterilization at
time o delivery, scheduling convenience, a preerence
or elective repeat cesarean delivery over emergency
cesarean delivery or operative vaginal delivery, the desire
to avoid labor pain, and ear o an unsuccessul trial o
labor have been identifed as reasons or preerring a
scheduled repeat cesarean delivery. The role o other
actors in womens preerencesincluding how the risk o
uterine rupture is viewed, sociodemographic status, social
norms, values, and beliesare less well understood.
With regard to health care provider preerences, ew dataexist to assess how obstetric providers view oering both
options (trial o labor and elective repeat cesarean delivery)
to their patients (holding other actors constant such as
liability concerns or past experience) and the conditions
under which they would eel comortable engaging their
patients in a thoughtul process o shared decisionmaking.
6. What Are the Critical Gaps in theEvidence or Decisionmaking, andWhat Are the Priority InvestigationsNeeded to Address These Gaps?
Critical gap 1: There is a need or uniorm and simple-
to-use defnitions that would be common to all datacollection. We recommend a standardized and systematic
use o defnitions or short-term and long-term maternal
and neonatal outcomes.
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Critical gap 2: There appear to be persistent racial/
ethnic, geographic, and socioeconomic dierences in
the rate o trial o labor and VBAC compared with elective
repeat cesarean delivery. We recommend investigation tounderstand the reasons or these dierences.
Critical gap 3: The actors that aect the course o labor
and its clinical management are incompletely understood.
We recommend well-designed clinical studies on practice
variation, provider type and setting, and intrapartum
management including induction methods. Methodologies
should be developed that address the challenges o
conducting studies based on plans or delivery, which
can change during the course o pregnancy.
Critical gap 4: Comparative long-term maternal and
perinatal biological and psychosocial outcomes ollowing
VBAC, unsuccessul trial o labor, and elective repeat
cesarean delivery are not well understood. We recommend
well-designed studies to identiy and describe these
outcomes so adverse consequences can be mitigatedor prevented.
Critical gap 5: The comparative eects that VBAC,
unsuccessul trial o labor, and elective repeat cesarean
delivery have on breasteeding practices are not well
understood. We recommend well-designed studies to
identiy these eects so adverse eects can be mitigated
or prevented.Critical gap 6:A variety o nonmedical actors aect
the availability and management o trial o labor, but
they have not been well studied. Access to sae trial
o labor appears to be restricted by actors such as
geography, workorce availability and training, proessional
association guidelines, type o maternity care provider,
liability concerns, health insurance, and institutional
policy. We recommend well-designed studies to better
understand these actors and to test clinical, institutional,
or policy interventions to increase access to sae trial
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o labor. Best practice models, such as those that
incorporate risk stratifcation in orming policies or
oering trial o labor and simulation training, should be
developed and careully assessed with an eye towardstheir widespread adoption.
Critical gap 7: The current medical-legal environment
including provider perceptions o and experience with
proessional liabilityexerts a chilling eect on the
availability o trial o labor. We recommend a series
o clinical and policy-relevant studies to develop
interventions to reduce this barrier.
Critical gap 8:The inormed consent process or trial
o labor and elective repeat cesarean delivery should be
evidence-based, minimize bias, and incorporate a strong
emphasis on the values and preerences o pregnant
women. We recommend interproessional collaboration to
refne, validate, and implement decisionmaking and risk
assessment tools, as well as inormed consent templates
that are inormative and reliable, and that can be welldocumented. These tools should also communicate
absolute risk in easily understood terms.
Critical gap 9: National and state-level surveillance o
actors associated with trial o labor are lacking. We
recommend that all states adopt the 2003 Standard
Certifcate o Live Birth and include questions in PRAMS
about decisions regarding method o delivery, laborinduction, and the role o the maternity care provider
and mother (and partner) in the decisionmaking process
rom early pregnancy through delivery.
Critical gap 10:There is insufcient inormation on
actors increasing VBAC among low-risk women.
We recommend high-quality clinical studies o well-
selected, low-risk women with sufcient statistical
power to characterize risks or unsuccessul trial
o labor in this population.
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Conclusions
Given the available evidence, trial o labor is a reasonable
option or many pregnant women with one prior low
transverse uterine incision. The data reviewed in this
report show that both trial o labor and elective repeat
cesarean delivery or a pregnant woman with one prior
transverse uterine incision have important risks and
benefts and that these risks and benefts dier or the
woman and her etus. This poses a proound ethical
dilemma or the woman as well as her caregivers,
because beneft or the woman may come at the price
o increased risk or the etus and vice versa. This
conundrum is worsened by the general paucity o high-
level evidence about both medical and nonmedical
actors, which prevents the precise quantifcation o
risks and benefts that might help to make an inormed
decision about trial o labor compared with elective
repeat cesarean delivery. We are mindul o these
clinical and ethical uncertainties in making the ollowingconclusions and recommendations.
One o our major goals is to support pregnant women
with one prior transverse uterine incision to make
inormed decisions about trial o labor compared with
elective repeat cesarean delivery. We recommend
clinicians and other maternity care providers use the
responses to the six questions, especially questions
3 and 4, to incorporate an evidence-based approachinto the decisionmaking process. Inormation, including
risk assessment, should be shared with the woman at
a level and pace that she can understand. When trial o
labor and elective repeat cesarean delivery are medically
equivalent options, a shared decisionmaking process
should be adopted and, whenever possible, the womans
preerence should be honored.
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We are concerned about the barriers that women ace in
gaining access to clinicians and acilities that are able and
willing to oer trial o labor. Given the low level o evidence
or the requirement or immediately available surgicaland anesthesia personnel in current guidelines, we
recommend that the American College o Obstetricians
and Gynecologists and the American Society o
Anesthesiologists reassess this requirement with specifc
reerence to other obstetric complications o comparable
risk, risk stratifcation, and in light o limited physician and
nursing resources. Healthcare organizations, physicians,
and other clinicians should consider making public theirtrial o labor policies and VBAC rates, as well as their
plans or responding to obstetric emergencies. We
recommend that hospitals, maternity care providers,
healthcare and proessional liability insurers, consumers,
and policymakers collaborate on the development o
integrated services that could mitigate or even eliminate
current barriers to trial o labor.
We are concerned that medical-legal considerations
add to, and in many instances exacerbate, these
barriers to trial o labor. Policymakers, providers, and
other stakeholders must collaborate in developing and
implementating appropriate strategies to mitigate the
chilling eect the medical-legal environment has on
access to care.
High-quality research is needed in many areas. Wehave identifed areas that need attention in response to
question 6. Research in these areas should be given
appropriate priority and should be adequately unded
especially studies that would help to characterize more
precisely the short-term and long-term maternal, etal,
and neonatal outcomes o trial o labor and elective
repeat cesarean delivery.
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Consensus Development Panel
F. Gary Cunningham, M.D.Panel and
Conerence ChairpersonBeatrice and Miguel Elias
Distinguished Chair inObstetrics and Gynecology
ProessorDepartment o Obstetrics and
GynecologyUniversity o Texas Southwestern
Medical Center at DallasDallas, Texas
Shrikant I. Bangdiwala, Ph.D.ProessorDepartment o Biostatistics,
Research TrackGillings School o Global
Public HealthUniversity o North Carolina
at Chapel HillChapel Hill, North Carolina
Sarah S. Brown, M.S.P.H.Chie Executive Ofcer
The National Campaignto Prevent Teen andUnplanned Pregnancy
Washington, DC
Thomas Michael Dean, M.D.Chie o Sta
Avera Weskota MemorialMedical Center
Sta PhysicianHorizon Health Care, Inc.Wessington Springs,
South Dakota
Marilynn Frederiksen, M.D.Associate Proessor o Clinical
Obstetrics and GynecologyFeinberg School o MedicineNorthwestern UniversityChicago, Illinois
Carol J. Rowland Hogue,Ph.D., M.P.H.
Jules & Uldeen Terry Proessor
o Maternal and Child HealthProessor o EpidemiologyDirectorWomens and Childrens CenterRollins School o Public HealthEmory University
Atlanta, Georgia
Tekoa King, CNM, M.P.H., FACNMAssociate Clinical Proessor
Department o Obstetrics,Gynecology, andReproductive Sciences
University o Caliornia,San Francisco
Deputy EditorJournal o Midwiery &
Womens HealthSan Francisco, Caliornia
Emily Spencer Lukacz, M.D., M.A.S.Associate ProessorClinical Reproductive MedicineUniversity o Caliornia,
San DiegoLa Jolla, Caliornia
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Laurence B. McCullough, Ph.D.Dalton Tomlin Chair in Medical
Ethics and Health PolicyProessor o Medicine and
Medical EthicsAssociate Director or EducationCenter or Medical Ethics
and Health PolicyBaylor College o MedicineHouston, Texas
Wanda Nicholson, M.D., M.P.H.,M.B.A.
Associate Proessor
Department o Obstetricsand GynecologyUniversity o North Carolina
at Chapel HillChapel Hill, North Carolina
Nancy Frances Petit, M.D.Chairperson, Division
o ObstetricsSt. Francis Hospital
Sta Obstetrician-GynecologistSt. Francis OB/GYN CenterNewark, DelawareFacultyUniormed Services University
o Health SciencesBethesda, Maryland
SpeakersDavid J. Birnbach, M.D., M.P.H.ProessorDepartments o Anesthesiology,
Obstetrics and Gynecology,and Public Health
Executive Vice ChairmanDepartment o Anesthesiology
Associate Dean and DirectorCenter or Patient SaetyMiller School o MedicineUniversity o MiamiMiami, Florida
Jerey Lynn Probstfeld, M.D.Adjunct Proessor o EpidemiologySchool o Public HealthProessor o Medicine (Cardiology)
Clinical Trials Service UnitUniversity o WashingtonSchool o Medicine
Seattle, Washington
Adele C. Viguera, M.D., M.P.H.Associate DirectorPerinatal and Reproductive
Psychiatry ProgramNeurological Institute
Cleveland ClinicCleveland, Ohio
Cynthia A. Wong, M.D.Proessor and Vice ChairpersonChie o Obstetrical AnesthesiaDepartment o AnesthesiologyNorthwestern UniversityFeinberg School o MedicineChicago, Illinois
Sheila Cohen Zimmet, R.N., J.D.Senior Associate Vice President
or Regulatory AairsGeorgetown University
Medical CenterWashington, DC
Emmanuel Bujold, M.D., M.Sc,FRCSC
Associate ProessorMaternal Fetal Medicine and
Perinatal EpidemiologyJeanne et Jean-Louis Lvesque
Research ChairDepartment o Obstetrics
and GynaecologyFaculty o MedicineLaval UniversityQubecCANADA
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Karen B. Eden, Ph.D.Investigator/Associate ProessorDepartment o Medical
Inormatics and Clinical
EpidemiologySchool o MedicineOregon Health and
Science UniversityPortland, Oregon
Cathy Emeis, Ph.D., CNMInvestigator/Assistant ProessorDepartment o Primary CareSchool o Nursing
Oregon Health andScience UniversityPortland, Oregon
Kimberly D. Gregory, M.D., M.P.H.Vice ChairpersonWomens Healthcare Quality and
Perormance ImprovementDepartment o Obstetrics
and Gynecology
Cedars-Sinai Medical CenterLos Angeles, Caliornia
William A. Grobman, M.D., M.B.A.Associate ProessorDivision o Maternal
Fetal MedicineDepartment o Obstetrics
and GynecologyFeinberg School o Medicine
Northwestern UniversityChicago, Illinois
Jeanne-Marie Guise, M.D., M.P.H.Principal Investigator/
Associate ProessorDepartments o Obstetrics
and Gynecology, andMedical Inormatics andClinical Epidemiology
School o MedicineOregon Health andScience University
Portland, Oregon
Lucky Jain, M.D., M.B.A.Richard W. Blumberg
Proessor and ExecutiveVice Chairperson
Department o PediatricsEmory UniversitySchool o Medicine
Atlanta, Georgia
Miriam Kuppermann, Ph.D., M.P.H.ProessorDepartments o Obstetrics,
Gynecology, & ReproductiveSciences, and Epidemiology
& BiostatisticsUniversity o Caliornia,San Francisco
San Francisco, Caliornia
Mark B. Landon, M.D.Proessor and DirectorDivision o Maternal-Fetal
MedicineDepartment o Obstetrics
and GynecologyThe Ohio State UniversityCollege o Medicine
Columbus, Ohio
Mona T. Lydon-Rochelle, Ph.D.,M.P.H., CNM
Associate Proessor andPerinatal Epidemiologist
National Perinatal
Epidemiology CentreAnu Research CentreDepartments o Obstetrics
and Gynaecology, andEpidemiology & Public Health
University College CorkCork University
Maternity HospitalCorkIRELAND
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Anne Drapkin Lyerly, M.D., M.A.Associate ProessorDepartment o Obstetrics
and Gynecology
Core FacultyTrent Center or Bioethics,Humanities, and Historyo Medicine
Duke UniversityDurham, North Carolina
George A. Macones, M.D., M.S.C.E.Proessor and ChairpersonDepartment o Obstetrics
and GynecologyWashington UniversitySchool o Medicine
St. Louis, Missouri
Howard Minko, M.D.Distinguished Proessor o
Obstetrics and GynecologyState University o New York
Downstate Medical Center
ChairpersonDepartment o Obstetricsand Gynecology
Maimonides Medical CenterBrooklyn, New York
T. Michael D. OShea, M.D., M.P.H.ProessorDepartment o PediatricsChie
Department o Neonatal& Perinatal MedicineNeonatology Division
o PediatricsSchool o MedicineWake Forest UniversityWinston-Salem, North Carolina
Rita RubinMedical Reporter
USA TODAYMcLean, Virginia
Caroline Signore, M.D., M.P.H.Medical OfcerPregnancy and
Perinatology Branch
Eunice Kennedy ShriverNational Institute o Child Health andHuman Development
National Institutes o HealthBethesda, Maryland
Robert M. Silver, M.D.Proessor and ChieDivision o Maternal-Fetal
MedicineDepartment o Obstetricsand Gynecology
University o UtahHealth Sciences Center
Salt Lake City, Utah
Michael L. Socol, M.D.Thomas J. Watkins
Memorial Proessor
and Vice ChairpersonDepartment o Obstetricsand Gynecology
Division o Maternal-FetalMedicine
Feinberg School o MedicineNorthwestern UniversityChicago, Illinois
Chet Edward Wells, M.D.
ProessorDepartment o Obstetricsand Gynecology
University o TexasSouthwestern MedicalCenter at Dallas
Dallas, Texas
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Planning Committee
Duane Alexander, M.D.Planning Committee
ChairpersonDirectorEunice Kennedy ShriverNa
tional Instituteo Child Health and HumanDevelopment
National Institutes o HealthBethesda, Maryland
Caroline Signore, M.D., M.P.H.Planning Committee
ChairpersonMedical OfcerPregnancy and
Perinatology BranchEunice Kennedy Shriver
National Institute o Child Health and
Human DevelopmentNational Institutes o HealthBethesda, Maryland
Lisa Ahramjian, M.S.Communications SpecialistOfce o Medical Applications
o ResearchOfce o the DirectorNational Institutes o Health
Bethesda, Maryland
Shilpa Amin, M.D., M.Bsc., FAAFPMedical OfcerEvidence-based Practice
Centers ProgramCenter or Outcomes
and EvidenceAgency or Healthcare
Research and Quality
Rockville, Maryland
David J. Birnbach, M.D., M.P.H.ProessorDepartments o Anesthesiology,
Obstetrics and Gynecology,and Public Health
Executive Vice ChairmanDepartment o AnesthesiologyDirectorCenter or Patient Saety
and Associate Dean
Miller School o MedicineUniversity o MiamiMiami, Florida
Beth Collins Sharp, Ph.D., R.N.DirectorEvidence-based Practice
Centers ProgramCenter or Outcomes
and Evidence
Agency or HealthcareResearch and Quality
Rockville, Maryland
Paul A. Cotton, Ph.D., R.D.Program DirectorHealth Behavior and
Minority HealthDivision o Extramural ActivitiesNational Institute o
Nursing ResearchNational Institutes o HealthBethesda, Maryland
F. Gary Cunningham, M.D.Panel and Conerence
ChairpersonBeatrice and Miguel Elias
Distinguished Chair inObstetrics and Gynecology
ProessorObstetrics and GynecologyUniversity o Texas Southwestern
Medical Center at DallasDallas, Texas
Planning Committee members provided their input at a meeting heldAugust 1214, 2008. The inormation provided here was accurate at thetime o that meeting. 39
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Lata S. Nerurkar, Ph.D.Senior Advisor or the Consensus
Development ProgramOfce o Medical Applications
o ResearchOfce o the DirectorNational Institutes o HealthBethesda, Maryland
Judith P. Rooks, CNM, M.P.H., M.S.American College
o Nurse-MidwivesPortland, Oregon
Susan C. Rossi, Ph.D., M.P.H.Deputy DirectorOfce o Medical Applications
o ResearchOfce o the DirectorNational Institutes o HealthBethesda, Maryland
James R. Scott, M.D.Editor-In-Chie
Obstetrics and GynecologyProessor and Chair EmeritusDepartment o Obstetrics
and GynecologyUniversity o Utah
Medical CenterSalt Lake City, Utah
Robert M. Silver, M.D.ProessorDivision Chie o Maternal-Fetal
Medicine
Department o Obstetricsand GynecologyUniversity o Utah
Health Sciences CenterSalt Lake City, Utah
Catherine Y. Spong, M.D.ChiePregnancy and
Perinatology Branch
Eunice Kennedy ShriverNational Institute o Child Health andHuman Development
National Institutes o HealthBethesda, Maryland
Linda J. Van Marter, M.D., M.P.H.Associate Proessor
o Pediatrics
Harvard Medical SchoolChildrens HospitalBoston, Massachusetts
Planning Committee members provided their input at a meeting heldAugust 1214, 2008. The inormation provided here was accurate at thetime o that meeting. 41
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Conerence Sponsors
Eunice Kennedy Shriver Ofce o Medical Applications
National Institute o o ResearchChild Health and Human Jennier M. Croswell, M.D., M.P.H.Development Acting Director
Alan Guttmacher, M.D.Acting Director
Conerence Cosponsors
National Institute o Ofce o Research on
Nursing Research Womens HealthPatricia Grady, Ph.D., R.N., Vivian W. Pinn, M.D.
FAAN Associate Director or ResearchDirector on Womens Health
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