Table 1. Comparison of National guidelines’ recommendations
ACOG Vaginal Birth After Previous
Cesarean Delivery (August 2010)~
Antenatal Counseling
and Informed consent
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Most women with one
previous cesarean delivery
with a low-transverse incision
are candidates for and should
be counseled about VBAC and
offered TOLAC. (Level A)
Women with two previous low
transverse cesarean deliveries
may be considered candidates
for TOLAC. (Level B)
Women with one previous
cesarean delivery with a low
transverse incision, who are
otherwise appropriate
candidates for twin vaginal
delivery, may be considered
candidates for TOLAC. (Level
B)
After counseling, the ultimate
decision to undergo TOLAC or
a repeat cesarean delivery
should be made by the patient
in consultation with her health
care provider. The potential
risks and benefits of both
TOLAC and elective repeat
cesarean delivery should be
discussed. Documentation of
counseling and the
management plan should be
included in the medical
record. (Level C)
SOGC Guidelines for Vaginal
Birth After Previous Caesarean
Birth
(February 2005)^
 Provided there are no
contraindications, a woman
with 1 previous
transverse low-segment
Caesarean section should be
offered a trial of labour (TOL)
with appropriate discussion
of maternal and perinatal
risks and benefits. The
process of informed consent
with
appropriate documenta-tion
should be an important part
of the birth
plan in a woman with a
previous Caesarean section
(Level B).
 The intention of a woman
undergoing a TOL after
Caesarean section should be
clearly stated, and
documentation of the
previous uterine scar should
be clearly marked on the
prenatal record (Level B).
 Each hospital should have a
written policy in place
regarding the notification
and (or) consultation for the
physicians responsible for a
possible timely Caesarean
section (Level B).
 Women delivering within 18
to 24 months of a Caesarean
section should be counseled
about an increased risk of
uterine rupture in labour
(Level B).
 Every effort should be made
to obtain the previous
Caesarean section operative
report to determine the type
of uterine incision used. In
situations where the scar is
unknown, information
RCOG Birth After Previous
Caesarean Birth
(February
2007)*
 Women considering their
options for birth after a
single previous caesarean
should be informed that,
overall, the chances of
successful planned VBAC
are 72–76%. (Level B)
Delivery resources and
facilities
Risks and benefits
 A trial of labor after previous
cesarean delivery should be
undertaken at facilities
capable of emergency
deliveries. Because of the risks
associated with TOLAC and
that uterine rupture and other
complications may be
unpredictable, the College
recommends that TOLAC be
undertaken in facilities with
staff immediately available to
provide emergency care.
When resources for
immediate cesarean delivery
are not available, the College
recommends that health care
providers and patients
considering TOLAC discuss the
hospital's resources and
availability of obstetric,
pediatric, anesthetic, and
operating room staffs.
Respect for patient autonomy
supports that patients should
be allowed to accept
increased levels of risk,
however, patients should be
clearly informed of such
potential increase in risk and
management alternatives.
(Level C)
 None as a recommendation
concerning the
circumstances of the
previous delivery is helpful in
determining the likelihood of
a low transverse incision. If
the likelihood of a lower
transverse incision is high, a
TOL after Caesarean section
can be offered (Level B).
 For a safe labour after
Caesarean section, a woman
should deliver in a hospital
where a timely Caesarean
section is available. The
woman and her health care
provider must be aware of
the hospital resources and
the availability of obstetric,
anesthetic, pediatric, and
operating-room staff.(Level
A)


Suspected uterine rupture
requires urgent attention
and expedited
laparotomy to attempt to
decrease maternal and
perinatal morbidity and
mortality (Level A).
In the case of a TOL after
Caesarean, an approximate
time frame
of 30 minutes should be
 Women should be advised
that planned VBAC should
be conducted in a suitably
staffed and equipped
delivery suite, with
continuous intrapartum
care and monitoring and
available resources for
immediate caesarean
section and advanced
neonatal resuscitation.
(Level B)
 Women considering the
options for birth after a
previous caesarean should
be informed that planned
VBAC carries a risk of
uterine rupture of 22–
74/10,000. There is
virtually no risk of uterine
rupture in women
undergoing ERCS. (Level B)
 Women considering the
considered adequate in the
set-up of an
urgent laparotomy (Level
C).
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options for birth after a
previous caesarean should
be informed that planned
VBAC compared with ERCS
carries around 1%
additional risk of either
blood transfusion or
endometritis.(Level B)
Women considering
planned VBAC should be
informed that this decision
carries a 2–3/10,000
additional risk of birthrelated perinatal death
when compared with ERCS.
The absolute risk of such
birth-related perinatal loss
is comparable to the risk
for women having their
first birth. (Level B)
Women considering the
options for birth after a
previous caesarean should
be informed that planned
VBAC carries an 8/10,000
risk of the infant
developing hypoxic
ischaemic encephalopathy.
The effect on the longterm outcome of the infant
upon experiencing HIE is
unknown. (Level B)
Women considering the
options for birth after a
previous caesarean should
be informed that
attempting VBAC probably
reduces the risk that their
baby will have respiratory
problems after birth: rates
are 2–3% with planned
VBAC and 3–4% with ERCS.
(Level B)
Women considering the
options for birth after a
previous caesarean should
be informed that the risk
of anaesthetic
complications is extremely
low, irrespective of
whether they opt for
planned VBAC or ERCS.
Fetal Heart Rate
monitoring
 None as a recommendation

Continuous electronic fetal
monitoring of women
attempting a TOL
after Caesarean section is
recommended (Level A).
Induction and
augmentation of labor


Medical induction of labour
with oxytocin may be
associated with an
increased risk of uterine
rupture and should be used
carefully after
appropriate counseling
(Level B).
Medical induction of labour
with prostaglandin E2
(dinoprostone) is associated
with an increased risk of
uterine rupture and should
not be used except in rare
circumstances and after
appropriate counseling
(Level B).
Medical induction of labour
with oxytocin may be
associated with an
increased risk of uterine
rupture and should be used
carefully after appropriate
counseling (Level B).
Oxytocin augmentation is
not contraindicated in
women undergoing a TOL
after Caesarean section
(Level A).
Prostaglandin E1
(misoprostol) is associated
with a high risk of uterine
rupture and should not be
used as part of a TOL after
Caesarean section (Level A).
A foley catheter may be
safely used to ripen the
Induction of labor for
maternal or fetal indications
remains an option in women
undergoing TOLAC. (Level B)
 Misoprostol should not be used
for third trimester cervical
ripening or labor induction in
patients who have had a
cesarean delivery or major
uterine surgery. (Level A)
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(Level B)
 Women considering the
options for birth after a
previous caesarean should
be informed that ERCS may
increase the risk of serious
complications in future
pregnancies. (Level B)
 Women should be advised
to have continuous
electronic fetal monitoring
following the onset of
uterine contractions for
the duration of planned
VBAC. (Level B)
 Women should be
informed of the two- to
three-fold increased risk of
uterine rupture and
around 1.5-fold increased
risk of caesarean section in
induced and/or augmented
labours compared with
spontaneous labours.
(Level B)
Success Rate
Contraindications and
special circumstances
 None as a recommendation
 External cephalic version for
breech presentation is not
contraindicated in women with
a prior low transverse uterine
incision who are at low risk for
adverse maternal or neonatal
outcomes from external
cephalic version and TOLAC.
(Level B)
 Those at high risk for
complications (eg, those with
previous classical or T-incision,
prior uterine rupture, or
extensive transfundal uterine
surgery) and those in whom
vaginal delivery is otherwise
contraindicated (eg, those with
placenta previa) are not
generally candidates for
planned TOLAC. (Level B)
 TOLAC is not contraindicated
for women with previous
cesarean delivery with an
unknown uterine scar type
unless there is a high clinical
suspicion of a previous classical
uterine incision. (Level B)
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
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
cervix in a woman planning
a TOL after Caesarean
section (Level A).
The available data suggest that  None as a
a trial of labour in women
recommendation
with more than 1 previous
Caesarean section is likely to
be successful but is
associated with a higher risk
of uterine rupture (Level B).
Multiple gestation is not a
 Women with a previous
contraindication to TOL
uterine incision other than
after Caesarean section
an uncomplicated low
(Level B).
transverse caesarean
section incision who wish
Diabetes mellitus is not a
to consider vaginal birth
contraindication to TOL
should be assessed by a
after Caesarean section
consultant with full access
(Level B).
to the details of the
Suspected fetal macrosomia
previous surgery. (Level C)
is not a contraindication to
TOL after Caesarean section  Women with a prior
history of two
(Level B).
uncomplicated low
Postdatism is not a
transverse caesarean
contraindication to a TOL
sections, in an otherwise
after Caesarean section
uncomplicated pregnancy
(Level B).
at term, with no
contraindication for
vaginal birth, who have
been fully informed by a
consultant obstetrician,
may be considered suitable
for planned VBAC. (Level B)
 Women who are preterm
and considering the
options for birth after a
previous caesarean should
be informed that planned
preterm VBAC has similar
success rates to planned
term VBAC but with a
lower risk of uterine
rupture. (Level B)
 A cautious approach is
advised when considering
planned VBAC in women
with twin gestation, fetal
macrosomia and short
interdelivery interval, as
there is uncertainty in the
safety and efficacy of
planned VBAC in such
Anesthesia
 Epidural analgesia for labor
may be used as part of TOLAC.
(Level A)
situations. (Level C)
 The routine use of
intrauterine pressure
catheters in the early
detection of uterine scar
rupture is not
recommended. (Level C)
Epidural anaesthesia is not
contraindicated in planned
VBAC. (Level C)
SOGC, Society of Obstetricians and Gynaecologists of Canada; RCOG, Royal College of Obstetricians and
Gynaecologists
The grade of recommendation is in parenthesis.
~ American College of Obstetricians and Gynecologist; Vaginal Birth After Previous Cesarean Delivery. Practice
Bulletin No. 115, 2010 (reference #).
^ Society of Obstetricians and Gynaecologists of Canada; Guidelines for Vaginal Birth After Previous Caesarean Birth
Clinical Practice guideline, No. 155, 2005 (reference #).
* Royal College of Obstetricians and Gynaecologists: Birth After Previous Caesarean Birth: Green-top Guideline No.
45, February 2007 (reference #).