Vaginal birth after cesarean section

Vaginal birth after cesarean section
(VBAC)
Presenter
Dr. Hem Nath Subedi
Resident, OBGYN
COMS-TH, Bharatpur

• Few issues in modern obstetrics have been as controversial
as management of the woman who has had a prior cesarean
delivery.1
• For many decades, a scarred uterus was believed by most
to contraindicate labor out of fear of uterine rupture.1
• In 1916 Cragnin made his famous oft-quoted and now
seemingly excessive pronouncement, “Once a cesarean
always a cesarean.”1
1)prior cesarean delivery In: William's obstetrics, 23rd edition, New York, Mc Graw Hill, 2010;pp 565-576
2)Vaginal birth After Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-276
2

• In 1920s the technique of low transverse uterine incision was
introduced by Kerr.1
• A large number of women may have successful and safe
vaginal birth after cesarean (VBAC) with reported figures of
70% to 80% (Flamm etal 1990).2
• American College of Obstetricians and Gynecologist concurs
and states , ‘Most women with one previous cesarean
delivery with a low transverse incision are candidates for and
should be counseled about VBAC and offered Trial of
Labour after Cesarean (TOLAC) (ACOG 2010).2
2)Vaginal birth After Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-276 3

1)prior cesarean delivery In: William's obstetrics, 23rd edition, New York, Mc Graw Hill, 2010;pp 565-576 2)Vaginal birth After
Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-276
4

Pregnant women with a previous cesarean section
can deliver in one of the following ways.2
• Trial of labour after previous cesarean delivery ending in
vaginal birth.
• Trial of labour after previous cesarean delivery ending in
emergency cesarean section.
• Planned elective repeat cesarean section(ERCS).
TOLAC should be undertaken in facilities with staff
immediately available to provide emergencycare.2
2)Vaginal birth After Cesarean Delivery In: The management of labour, 3rd edition, India Universities
Press,2011;pp 266-276
5

Maternal risk of TOLAC
Risk of uterine rupture.
• One of the major determinants of severe adverse outcome
associated with VBAC is whether uterine rupture occurs.2
• The incidence of this is generally estimated to be in region of
0.5% to 1.0%.2
• Considering all gestational ages, uterine rupture occurs in
approximately 325 per 1,00,000 women undergoing trial of
labour.2
• Maternal death from uterine rupture in planned VBAC occurs in
less than 1/1,00,000 cases in the developed countries. There may
be much higher in developing countries (Farmer et al ).2
2)Vaginal birth After Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-
276 6

Maternal risk of TOLAC
Risk associated with failed TOLAC.
• The major determinant of morbidity associated with a decision for
TOLAC is whether the attempt is successful.2
• In a study from Nigeria, failed VBAC was associated with higher
incidence of chorioamnionitis, PPH, Blood transfusion, uterine
rupture, hysterectomy and composite major neonatal morbidities.2
• The risk factors which predicted failure were (obri et al 2010).2
– Younger age
– Lack of previous vaginal delivery
– Induction of labour
– Fetal weight>4kg
7

Risk of TOLAC to fetus/neonate
• The risk of perinatal death associated with TOLAC is
comparable to that of nulliparas in labour.2
• TOLAC carries a 2-3/10000 additional risk of birth related
perinatal death when compared with elective repeat cesarean
section (ERCS).2
• The rate of hypoxic-ischemic encephalopathy can increase
significantly with uterine rupture. However, it is important to
remember that this complication is also extremely rare.2
8

Candidate for a TOLAC
Some Factors for Consideration in Selection of Candidates for
Vaginal Birth after Cesarean Delivery (VBAC)
– One previous prior low-transverse cesarean delivery
– Clinically adequate pelvis
– No other uterine scars or previous rupture
– Physician immediately available throughout active labor capable of
monitoring labor and performing an emergency cesarean delivery
– Availability of anesthesia and personnel for emergency cesarean delivery
Reprinted, with permission, from American College of
Obstetricians and Gynecologists. Vaginal birth after previous
cesarean delivery. ACOG Practice Bulletin 54. Washington, DC:
ACOG; 2004.
10

Contraindication to TOLAC
• Due to higher absolute risks of uterine rupture or unknown
risks planned TOLAC is contraindicated in women with: 1
– Previous uterine rupture; risk of recurrent rupture is
unknown
– Previous high vertical classical cesarean section where the
uterine incision has involved the whole length of the
uterine corpus (200-900/10000) risk of uterine rupture.
– Three or more previous cesarean deliveries.
– Where the women herself refuses.
11

Factors influencing success of VBAC
• Type of prior uterine incision
• Prior uterine rupture
• Closure of prior incision
• Interdelivery interval
• Number of prior cesarean incisions
• Prior vaginal delivery
• Indication for prior cesarean delivery
• Fetal size
• Multifetal gestation
• Maternal obesity
13

14

Prior uterine rupture
• Women who have previously sustained a uterine rupture are at
increased risk for recurrence during a subsequent attempted
VBAC.
• Women with prior uterine rupture or classical or T-shaped
incision ideally should undergo repeat cesarean delivery when
fetal pulmonary maturity is assured, and preferably prior to the
onset of labour.
• Counseling regarding the hazards of unattended labor and
signs of possible uterine rupture.
15

Closure of prior incision
• Chapman (1997) and Tucker (1993) and their associates found
no relationship between a one- and two-layer closure and the
risk of subsequent uterine rupture.1
• Durnwald and Mercer (2003) also found no increased risk of
rupture, they reported that uterine dehiscence was more
common after single-layer closure.1
• Bujold and co-workers (2002) found that a single-layer closure
was associated with nearly a fourfold increased risk of rupture
compared with a double-layer closure.1,2
16

Interdelivery interval
• Having at least 24 months between the date of the last cesarean
birth and the due date for this pregnancy increases the chance of
successful VBAC and decreases the risk of uterine rupture.2
• Shipp and associates (2001) examined the relationship between
interdelivery interval and uterine rupture in 2409 women who
had one prior cesarean delivery. Uterine rupture developed in 29
women—1.4 percent. Interdelivery intervals of 18 months or less
were associated with a threefold increased risk of symptomatic
rupture during a subsequent trial of labor compared with intervals
greater than 18 months.1

Number of prior cesarean incisions
• It also seems logical that the risk of uterine rupture would
increase with the number of previous cesarean deliveries.1
• Miller and colleagues (1994) studied 12,707 such women
undergoing a trial of labor. They reported rupture rates of 0.6
percent following one cesarean delivery and 1.8 percent for
women with two prior cesarean deliveries.1
• Macones and associates (2005a) reported a twofold increase in
the rate of uterine rupture among women attempting trial of
labor after two prior cesarean deliveries—1.8 percent—
compared with those with one—0.9 percent.1
18

Prior vaginal delivery
• Previous vaginal birth, particularly previous VBAC , Is The
Single Best Predictor For Successful VBAC.2
• It is associated with an approximately 87% to 90% success
rate for planned VBAC.2
• The rate of rupture increases with each successive labour , but
a prior vaginal delivery also increases the chance of a
successful VBAC attempt.2
19

Indication for prior cesarean delivery
• The success rate for a trial of labor depends to some extent on
the indication for the previous cesarean delivery. 1
• In a large series reported by Wing and Paul (1999), 91 percent
of women whose first cesarean delivery was for breech
presentation subsequently delivered vaginally.1
• If fetal distress was the original indication, the success rate
was 84 percent.1
• Prior dystocia is an important predictor of vaginal delivery
after prior cesarean. In more than 1900 women, Peaceman and
associates (2006) found that those with dystocia as the original
indication had a significantly lower success rate compared
with those with other indications—54 versus 67 percent,
respectively.1
20

Fetal size
• It has not been conclusively proven that increasing fetal size
increases the risk for uterine rupture with VBAC.1
• Zelop and associates (2001) compared the outcomes of almost
2750 women undergoing a trial of labor of whom 1.1 percent
had a uterine rupture. The rate increased—albeit not
significantly—with increasing fetal weight—1.0 percent for
<4000 g, 1.6 percent for >4000 g, and 2.4 percent for >4250
g.1
• Elkousy and colleagues (2003) reported that for women
attempting VBAC who had no previous vaginal deliveries, the
relative risk of rupture doubled if birth weight was >4000 g.1

Multifetal gestation
• Twin pregnancy does not appear to increase the risk of uterine
rupture with VBAC.1
• Ford and associates (2006) analyzed the outcomes of 1850
such women with a prior cesarean delivery who attempted a
trial of labor. The uterine rupture rate was 0.9 percent, and the
rate of successful vaginal delivery was 45 percent.1
• Cahill (2005) and Varner (2007) and their colleagues reported
rupture rates of 0.7 to 1.1 percent and vaginal delivery rates of
75 to 85 percent.1

Maternal obesity
• Obesity decreases the success of VBAC.1
• Hibbard and colleagues (2006) reported the following vaginal
delivery rates: 85 percent with a normal body mass index
(BMI), 78 percent with a BMI between 25 and 30, 70 percent
with a BMI between 30 and 40, and 61 percent with a BMI of
40 or more.1

Antenatal care
• Counseling regarding mode of delivery should ideally start at
the time of the sentinel cesarean .2
• Women should be offered information regarding the need for
the first cesarean and implication it may have for future
pregnancies and deliveries.2
• Identify ,at the first antenatal visit all women who have had a
previous cesarean section or have a uterine scar, a senior
consultant should assess them.2
24

Factors to note at booking visit include
• Number and type of previous uterine scars, indications for
prior cesarean section, there any puerperal complications,
gestation at time of prior cesarean section, interconception
interval and other associated medical problem.2
• Anticipated family size: this is important as the longer term
risks related to further repeat cesarean section scars med be
taken into consideration ( placenta previa, placenta accreta,
blood loss , transfusion, hysterectomy and mortality).2
• History of a successful vaginal delivery and whether this was
before or after the uterine scar. The rupture rate rises with each
successive labour but a prior vaginal delivery also increases
the chance of a successful VBAC attempt.
25

Antenatal counseling
• Women with a prior history of one uncomplicated LSCS , in an
otherwise uncomplicated pregnancy at term, with no contraindication
to vaginal birth, should be able to discuss the option of planned
VBAC and the alternative on an elective repeat cesarean.2
• The antenatal counseling of women with a prior cesarean birth should
be documented in the notes . A patient information leaflet should be
provide with the consultation.2
• A final decision for mode of birth should be agreed between the
woman and her obstetrician before the expected/planned delivery
date, ideally by 36weeks of gestation (flamm et al 1990).2
• Placenta previa/accreta should be excluded with USG. Identifying and
treating anemia early on is important in these women.
Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-276 26

If decision is made for TOLAC ,the woman
should be advised:
• To present to the obstetric unit early in labour or if there is
SROM occurs.2
• That the decision made in the antenatal clinic is not binding .2
• To have a clear understanding with the obstetric team which
states the boundaries of safe practice to which they have
agreed and indicate the circumstances under which they would
request that a repeat cesarean section be carried out.2
• Te decision should be clearly documented in the antenatal
records
27

Intrapartum Management
• Women who have had a previous cesarean section should
be offered care during labour in a unit where:
– There is immediate access to cesarean section.
– There are on site blood transfusion services or blood can be
obtained with in a reasonable amount of time.
– Facilities for continuous fetal heart monitoring are available,
preferably electronic fetal heart monitoring.
– Specialist obstetricians, anesthetists and pediatrician are
available round the clock
28

Continuous fetal monitoring
• Continuous electronic fetal monitoring is recommended
following the onset of uterine contractions for the duration of
TOLAC.2
• An abnormal CTG is the most consistent finding in uterine
rupture and is present in 55% to 87% of these events(guise et
al 2004).2
1)prior cesarean delivery In: William's obstetrics, 23rd edition, New York, Mc Graw Hill, 2010;pp 565-576 2)Vaginal birth
After Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-276 29

Partogram for progress of labour
• Partographic progress of labour enhances safety. A partogram,
in addition to monitoring progress of labour , enables effective
monitoring of maternal parameters like blood pressure and
pulse rate.2
• The duration of labour should be closely monitored with
special reference to alert and action line on partogram.
Prolongation of labour is an important sign of dystocia.2
2)Vaginal birth After Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp
266-276
30

Analgesia
• Epidural analgesia for labour may be used as part of TOLAC ,
and adequate pain relief may encourage women to choose
TOLAC (sakala et al 1990, flamm et al 1998).2
• In addition effective regional analgesia should not be expected
to mask signs and symptoms of uterine rupture, particularly
because the most common sign of rupture is FHR tracing
abnormalities.2
31

Early diagnosis of uterine rupture
• Early diagnosis of uterine scar rupture followed by expeditious
laparotomy and resuscitations essential to reduce associated
morbidity and mortality and infants.
• There is no single pathognomonic clinical feature that is indicative
of uterine rupture but the presence of any of the following
peripartum signs and symptoms should raise the concern of the
possibilities of uterine rupture (turner 2002)
– Abnormal CTG tracing, severe abdominal pain persisting in between
contractions, chest pain or shoulder tip pain, acute onset scar
tenderness, abnormal vaginal bleeding and hematuria, cessation of
previously efficient uterine activity, maternal tachycardia,
hypotension or shock, loss of station of the presenting part.
2)Vaginal birth After Cesarean Delivery In: The management of labour, 3rd edition, India Universities Press,2011;pp 266-
276
32

Delivery
• The length of the second stage should not exceed 2 hrs. one
hour to allow passive descent, but no more than one hour for
active pushing (or 30 minutes if the woman has had a prior
vaginal delivery).2
• Assisted delivery ,in the presence of a prior uterine scar,
should ideally only be performed by an experienced
consultant. This should be in the operating theatre with
provision for immediate cesarean section.2
• Excessive vaginal bleeding or signs of hypovolemia are
potential signs of uterine rupture and should prompt complete
evaluation of the genital tract (cahill etal 2005).2
Press,2011;pp 266-276 33

Role of induction and augmentation of labour in
VBAC
• Women with a previous cesarean should be informed of the
two to three fold increased risk of uterine rupture and around
1.5 fold increased risk of cesarean section in induced labours
compared with spontaneous labour.2
• Lydon-Rochelle and associates (2001) performed a
retrospective population-based study. They found that
induction of labor with prostaglandins for VBAC increased the
uterine rupture risk more than 15-fold compared with elective
repeat cesarean delivery.1
Press,2011;pp 266-276
34

Vaginal birth after cesarean section

Recommended

Recommended

More Related Content

What's hot

What's hot (20)

Similar to Vaginal birth after cesarean section

Similar to Vaginal birth after cesarean section (20)

More from hemnathsubedii

More from hemnathsubedii (12)

Vaginal birth after cesarean section