Vaginal Birth after Caesarean (VBAC) Max Brinsmead MB BS PhD May 2015.

Vaginal Birth after Caesarean(VBAC)

Max Brinsmead MB BS PhDMax Brinsmead MB BS PhD

May 2015May 2015

VBAC – The Controversy ““Once a Caesarean always a Caesarean”Once a Caesarean always a Caesarean”

• Edwin Cragin – 1916Edwin Cragin – 1916• In an era of classical CSIn an era of classical CS• Designed to prevent unnecessary primary CSDesigned to prevent unnecessary primary CS

For 60 years “Trial of (lower segment) For 60 years “Trial of (lower segment) scar” was standard British practicescar” was standard British practice

But repeat CS more common in the USBut repeat CS more common in the US Controversy broke out again in 2000Controversy broke out again in 2000 And it was all about fetal risksAnd it was all about fetal risks

VBAC – The ControversySmith et al from Cambridge UK in JAMA 2002Smith et al from Cambridge UK in JAMA 2002

Reviewed 313, 238 singleton births, 37 - 43w, Reviewed 313, 238 singleton births, 37 - 43w, cephalic presentation in the Scottish Morbidity cephalic presentation in the Scottish Morbidity Register 1992 -1997 excluding congenital Register 1992 -1997 excluding congenital malformations and found…malformations and found…

1. Rate of perinatal death 11 times higher for VBAC 1. Rate of perinatal death 11 times higher for VBAC compared to elective CScompared to elective CS

2. This is 2 times higher than for multiparas having a 2. This is 2 times higher than for multiparas having a vaginal birthvaginal birth

VBAC – The ControversyGuise et al from Portland Oregan in BMJ July 2004Guise et al from Portland Oregan in BMJ July 2004

Reviewed 568 publications on VBAC vs elective Reviewed 568 publications on VBAC vs elective CS but found only 71 had useful dataCS but found only 71 had useful data

Concluded that the additional risk of perinatal Concluded that the additional risk of perinatal death from attempted VBAC was 1.4 per 10,000 death from attempted VBAC was 1.4 per 10,000 (95 percent confidence limits 0 - 9.8)(95 percent confidence limits 0 - 9.8)

In only 5% of uterine ruptures did the baby dieIn only 5% of uterine ruptures did the baby die This means that one has to perform 7142 elective This means that one has to perform 7142 elective

CS to prevent one baby deathCS to prevent one baby death

This presentation will: Examine the advantages and disadvantages Examine the advantages and disadvantages

of VBACof VBAC Evaluate the risks to mother & babyEvaluate the risks to mother & baby Provide an evidence base for the safe Provide an evidence base for the safe

practice of VBAC...practice of VBAC...Patient selectionPatient selectionPreparation of patientsPreparation of patientsGuidelines for intrapartum careGuidelines for intrapartum care

Advantages of VBAC Greater maternal satisfactionGreater maternal satisfaction

• But it’s not all about “me”But it’s not all about “me”

Quicker recoveryQuicker recovery• But not alwaysBut not always

CheaperCheaper• But not much cheaper than elective CS and can But not much cheaper than elective CS and can

be much more costlybe much more costly

Less RDS for babiesLess RDS for babies• But greater risk of death & disabilityBut greater risk of death & disability

Less maternal morbidity and mortalityLess maternal morbidity and mortality• But these are rare with elective CSBut these are rare with elective CS

Advantages of VBAC - 2 More vaginal births in the futureMore vaginal births in the future

• But what’s the point if there’s only to be two But what’s the point if there’s only to be two kids!kids!

Less maternal depressionLess maternal depression• But there is no evidence that this is soBut there is no evidence that this is so

Breast feeding more likely to succeedBreast feeding more likely to succeed• Occurs in the delivery roomOccurs in the delivery room• Easier for mothers without wound pain Easier for mothers without wound pain

Avoids risks unique to CSAvoids risks unique to CS• But these are rareBut these are rare

Advantages of Elective CS Certainty of timingCertainty of timing

• That’s the modern way!That’s the modern way!

Certainty of outcomeCertainty of outcome• If I have a 30 – 50% chance of CS just do one!If I have a 30 – 50% chance of CS just do one!• Emergency CS more dangerousEmergency CS more dangerous

It’s Pain-freeIt’s Pain-free• More or less guaranteed!More or less guaranteed!

Often preferred by fathers & obstetriciansOften preferred by fathers & obstetricians• That’s a male thingThat’s a male thing

Advantages of Elective CS Protects the pelvic floorProtects the pelvic floor

• Controversial becauseControversial because• Some risk arises from the pregnancy itselfSome risk arises from the pregnancy itself• And CS may not be protectiveAnd CS may not be protective

Safer for babiesSafer for babies• But the absolute risk of VBAC is smallBut the absolute risk of VBAC is small

Avoids the risk of scar ruptureAvoids the risk of scar rupture• But there is much uncertainty about the But there is much uncertainty about the

frequency of this frequency of this • and the maternal and fetal risks and the maternal and fetal risks

VBAC Risk to the Fetus The rate of perinatal death is 11 x higher than The rate of perinatal death is 11 x higher than

for elective CSfor elective CS BUT…BUT… This risk is equivalent to that of being a fetus This risk is equivalent to that of being a fetus

to a Primigravidato a Primigravida The absolute risk is only 4.5 per 10,000 birthsThe absolute risk is only 4.5 per 10,000 births Confidence limits are wideConfidence limits are wide In the 2002 UK publication all emergency CS In the 2002 UK publication all emergency CS

were classified as attempted VBACwere classified as attempted VBAC

Maternal Risk from VBAC Meta analysis of risk of deathMeta analysis of risk of death

• 2.8 per 10,000 with trial of scar2.8 per 10,000 with trial of scar• 2.4 per 10,000 for elective CS2.4 per 10,000 for elective CS• No maternal death ever attributed to scar ruptureNo maternal death ever attributed to scar rupture

Scar ruptureScar rupture• Much confusion in the literature over the definitionMuch confusion in the literature over the definition• Rate of asymptomatic scar rupture the same whether Rate of asymptomatic scar rupture the same whether

VBAC or elect CSVBAC or elect CS• Overall rate approx. 0.5% or 1:200Overall rate approx. 0.5% or 1:200• Was 0.35% in the largest combined contemporary studyWas 0.35% in the largest combined contemporary study

HysterectomyHysterectomy• Additional risk from trial of scar is 3.4 per 10,000Additional risk from trial of scar is 3.4 per 10,000• Requires 2941 elective CS to prevent one hysterectomyRequires 2941 elective CS to prevent one hysterectomy

Patient selection for VBAC Type of previous CSType of previous CS

• "10% " risk of rupture from classical and T incisions"10% " risk of rupture from classical and T incisions• Myomectomy and HysterotomyMyomectomy and Hysterotomy

Indication for Previous CSIndication for Previous CS• But 50-75% of patients can VBAC after previous CS for But 50-75% of patients can VBAC after previous CS for

CPD!CPD!

Previous obstetric historyPrevious obstetric history• VBAC success >90% if there has been prior vaginal birthVBAC success >90% if there has been prior vaginal birth• Dilatation at the time of previous CSDilatation at the time of previous CS• Gestation at previous CS – was there a lower segment?Gestation at previous CS – was there a lower segment?

Number of previous CSNumber of previous CS• Increasing risk with increasing numberIncreasing risk with increasing number

Patient selection for VBAC -2 Time since previous CSTime since previous CS

• Risk of scar rupture is 2 – 3x greater if <18mRisk of scar rupture is 2 – 3x greater if <18m

Maternal weightMaternal weight• Miserable rates of VBAC for women >135 KgMiserable rates of VBAC for women >135 Kg

Lower uterine segment thicknessLower uterine segment thickness• No uterine ruptures if >4.5 mmNo uterine ruptures if >4.5 mm

Maternal AgeMaternal Age• Clear evidence for declining uterine performance with age Clear evidence for declining uterine performance with age

at first labourat first labour

Family history of labour performanceFamily history of labour performance• A field ripe for studyA field ripe for study

Patient selection for VBAC - 3 Size of the mother and babySize of the mother and baby

• But we are very bad at estimating thisBut we are very bad at estimating this

Other pregnancy problemsOther pregnancy problems• Should be assessed according to obstetric principlesShould be assessed according to obstetric principles

Engagement and cervical ripeningEngagement and cervical ripening• Best assessed at the onset of labourBest assessed at the onset of labour

Labour performanceLabour performance• That’s why it’s called trial of scarThat’s why it’s called trial of scar• Dilatation and descentDilatation and descent• Progress rather than arbitrary time limitsProgress rather than arbitrary time limits

Psychological FactorsPsychological Factors• The patient’s willingness and driveThe patient’s willingness and drive• The support providedThe support provided

More than one previous CS? Tahseen & Griffith BJOG Jan 2010 in a Tahseen & Griffith BJOG Jan 2010 in a

systematic analysis of available data and systematic analysis of available data and meta analysis concluded:meta analysis concluded:

1.1. Overall success 71.1%Overall success 71.1%2.2. Risk of scar rupture 1.36% (this is 3x greater than Risk of scar rupture 1.36% (this is 3x greater than

for one CS)for one CS)3.3. Perinatal risk is 0.09% (this is 3x greater than for Perinatal risk is 0.09% (this is 3x greater than for

one CS)one CS)4.4. The overall maternal morbidity was the same as The overall maternal morbidity was the same as

that for elective CS that for elective CS Hysterectomy, transfusion, febrile morbidity etcHysterectomy, transfusion, febrile morbidity etc

More than two previous CS? Cahill et al BJOG 2010 in a retrospective Cahill et al BJOG 2010 in a retrospective

cohort study 89 women with >2 previous cohort study 89 women with >2 previous CS concluded:CS concluded:

1.1. Overall success 79.8%Overall success 79.8%2.2. No cases of uterine ruptureNo cases of uterine rupture3.3. The overall maternal morbidity was the same as The overall maternal morbidity was the same as

that for elective CS that for elective CS Hysterectomy, transfusion, febrile morbidity etcHysterectomy, transfusion, febrile morbidity etc

Lower segment thickness and risk of scar rupture

Rozenberg et al Lancet 1996 Rozenberg et al Lancet 1996 studied 642 women with studied 642 women with ultrasound , measured the thinnest point of the lower ultrasound , measured the thinnest point of the lower segment against a filled bladder, then attempted VBAC:segment against a filled bladder, then attempted VBAC:

>4.5 mm - no ruptures or dehiscence (278)>4.5 mm - no ruptures or dehiscence (278) 3.6 - 4.5 mm 2% rate of scar rupture (177)3.6 - 4.5 mm 2% rate of scar rupture (177) 2.6 - 3.5 mm 10% rate of scar rupture (136)2.6 - 3.5 mm 10% rate of scar rupture (136) <2.6 mm 16% rate of scar rupture (51)<2.6 mm 16% rate of scar rupture (51)

Can be technically difficult particularly in obese womanCan be technically difficult particularly in obese womanVaginal and 3-dimensional measures promisingVaginal and 3-dimensional measures promising

VBAC for the Obese? Carrel et al (Am J OG in 2003) sCarrel et al (Am J OG in 2003) studied 70 women >200 lb, 70 tudied 70 women >200 lb, 70

who were 200-300 lb and 69 >300 lbwho were 200-300 lb and 69 >300 lb

81.8% success for those <200 lb81.8% success for those <200 lb 57.1% success for those 200-300 lb57.1% success for those 200-300 lb 13.3% success for those >300 lb13.3% success for those >300 lb Infection rate was:Infection rate was: 5.7% group 15.7% group 1 11.4% group 211.4% group 2 39% group 339% group 3 (Very similar results published in 2001)(Very similar results published in 2001)

VBAC for Older Women? Byfield et al Am J OG in 2004 sByfield et al Am J OG in 2004 studied 659 women <30 tudied 659 women <30

years age, 721 who were 30-35 years age and 370 >35 years age, 721 who were 30-35 years age and 370 >35 years ageyears age

72% success for those <3072% success for those <3071% success for those 30-3571% success for those 30-3565% success for those >3565% success for those >35 Scar rupture rate wasScar rupture rate was::2.0% group 12.0% group 11.1% group 21.1% group 21.4% group 31.4% group 3

Pregnancy Interval and Risk of Scar Rupture

Byfield et al Am J OG in 2002Byfield et al Am J OG in 2002 studied 1527 women who studied 1527 women who attempted VBAC at <12 to >36 months after previous CS:attempted VBAC at <12 to >36 months after previous CS:

4.8% ruptured for those <12m4.8% ruptured for those <12m 2.7% ruptured for those 13-24m2.7% ruptured for those 13-24m 0.9% ruptured for those 25-36m0.9% ruptured for those 25-36m 0.9% ruptured for those >36m0.9% ruptured for those >36m

Pregnancy Interval and Risk of Scar Rupture

Bujold & Gauthier Obstet Gynec in 2010Bujold & Gauthier Obstet Gynec in 2010 studied 1768 studied 1768 women who attempted VBAC after one previous CS:women who attempted VBAC after one previous CS:

4.8% ruptured for those <18m4.8% ruptured for those <18m 1.9% ruptured for those 18-24m1.9% ruptured for those 18-24m 1.3% ruptured for those >24m1.3% ruptured for those >24m

Also noted 7-fold increased rate of rupture Also noted 7-fold increased rate of rupture when the previous CS was a single layer when the previous CS was a single layer closureclosure

Single vs Double-layer closure at prior CS

Blumenfeld et al BJOG in 2010Blumenfeld et al BJOG in 2010 studied 127 women studied 127 women undergoing primary CS. undergoing primary CS.

At subsequent CS those who had a single At subsequent CS those who had a single layer closure had a 7-fold increased risk of layer closure had a 7-fold increased risk of bladder adhesions (RR=6.96, CI 1.72 – bladder adhesions (RR=6.96, CI 1.72 – 28.1)28.1)

Regardless of any other variation in surgical Regardless of any other variation in surgical techniquetechnique

Induction of Labour for VBAC?

Ravasia et al Am JOG 2000 sRavasia et al Am JOG 2000 studied 2119 women attempting tudied 2119 women attempting VBAC between 1992 and 1998 of whom 27% had an VBAC between 1992 and 1998 of whom 27% had an induction of labourinduction of labour

Spontaneous labour 0.45% scar rupture Spontaneous labour 0.45% scar rupture raterate

Induced labour 1.4% Induced labour 1.4% Cx ripening c PGs 2.9% Cx ripening c PGs 2.9% Cx ripening c Foley 0.7% Cx ripening c Foley 0.7% IOL not using PGs 0.7%IOL not using PGs 0.7%

Induction of Labour for VBAC -2?

Lyndan-Rochelle et al NEJM 2001 sLyndan-Rochelle et al NEJM 2001 studied all women tudied all women attempting VBAC between 1987 and 1996 in Washington attempting VBAC between 1987 and 1996 in Washington statestate

Rate of Scar RuptureRate of Scar Rupture No labour 1.6 per 1000No labour 1.6 per 1000 Spontaneous labour 5.2 " " Spontaneous labour 5.2 " " Induced labour (not PGs) 7.7 " " Induced labour (not PGs) 7.7 " " Induced with PGs 24.5 " " Induced with PGs 24.5 " "

However this study used ICD9 codes for identifying scar However this study used ICD9 codes for identifying scar rupture and these are only 40% accuraterupture and these are only 40% accurate

Induction of Labour for VBAC -3?

Lin & Rayner Am JOG 2004 sLin & Rayner Am JOG 2004 studied 3533 women attempting tudied 3533 women attempting VBAC after one or more CS, 2523 in spontaneous labour, VBAC after one or more CS, 2523 in spontaneous labour, 438 by elective CS, 430 induced with oxytocin and 142 438 by elective CS, 430 induced with oxytocin and 142 induced with Misoprostolinduced with Misoprostol

Rate of scar rupture was significantly higher Rate of scar rupture was significantly higher when labour was induced.when labour was induced.

No significant difference between oxytocin No significant difference between oxytocin (0.8%) and Misoprostol (1.1%)(0.8%) and Misoprostol (1.1%)

Induction of Labour for VBAC -4?

Dekkar et al studied 29,008 women attempting VBAC in Dekkar et al studied 29,008 women attempting VBAC in Australia 1998 – 2000 BJOG 117:1358 2010Australia 1998 – 2000 BJOG 117:1358 2010

Rate of scar rupture (complete & partial ) was: Rate of scar rupture (complete & partial ) was:

No labour 0.01%No labour 0.01%Spontaneous labour with no augmentation 0.15%Spontaneous labour with no augmentation 0.15%Labour augmented with oxytocin 1.91%Labour augmented with oxytocin 1.91%Induced using oxytocin 0.54%Induced using oxytocin 0.54%Induced using prostaglandins (PG’s) 0.68%Induced using prostaglandins (PG’s) 0.68%Induced with PG’s and oxytocin 0.88%Induced with PG’s and oxytocin 0.88%

Overall rate of successful VBAC 54.3%Overall rate of successful VBAC 54.3%

Canadian College Surgeons & Physicians Guidelines 1993 - 1

Trial of labour should be recommended to Trial of labour should be recommended to all women who have had only one previous all women who have had only one previous CS. Except for:CS. Except for:Previous classical, T or unknown uterine incisionPrevious classical, T or unknown uterine incision

Previous hysterotomy or full thickness myomectomyPrevious hysterotomy or full thickness myomectomyPrevious uterine rupturePrevious uterine ruptureAny contraindication to labour in this pregnancy eg Any contraindication to labour in this pregnancy eg placenta previa, transverse lie etc.placenta previa, transverse lie etc.

The wish of the patient is paramountThe wish of the patient is paramount (and the partner should ideally also be involved)(and the partner should ideally also be involved)

Canadian College Surgeons & Physicians Guidelines 1993 - 2

The patient should be made aware of the The patient should be made aware of the hospital’s resources and any limitationshospital’s resources and any limitations

The previous obstetric record should be The previous obstetric record should be consultedconsulted

Consultation with a specialist obstetrician is Consultation with a specialist obstetrician is not mandatorynot mandatory

Induction of labour with oxytocin or Foley Induction of labour with oxytocin or Foley catheter is acceptablecatheter is acceptable

Augmentation with oxytocin is acceptable but Augmentation with oxytocin is acceptable but caution required if arrest has occurred in the caution required if arrest has occurred in the active phase of labouractive phase of labour

Canadian College Surgeons & Physicians Guidelines 1993 - 3

Continuous EFM required only when when Continuous EFM required only when when induction or augmentation of labour is usedinduction or augmentation of labour is used

The problem of false positivesThe problem of false positives No evidence that it is a specific indicator of scar No evidence that it is a specific indicator of scar

rupturerupture

Epidural anaesthesia not contraindicatedEpidural anaesthesia not contraindicated Twins not contraindicatedTwins not contraindicated Suspected fetal macrosomia & diabetes not Suspected fetal macrosomia & diabetes not

contraindicatedcontraindicated

My guidelines for VBAC - 1 Patients are counselled that VBAC is Patients are counselled that VBAC is notnot

appropriate if:appropriate if:• There is a classical, T-shaped or unknown There is a classical, T-shaped or unknown

uterine incisionuterine incision

• More than one CS has been performedMore than one CS has been performed

• The previous CS was performed for failure to The previous CS was performed for failure to progress in the active phase of labour i.e. >4 cm progress in the active phase of labour i.e. >4 cm dilateddilated

• Their BMI is >35Their BMI is >35 Patients accepted outside of these guidelines on a case- Patients accepted outside of these guidelines on a case-

by-case basis.by-case basis.

My guidelines for VBAC - 2 Patients who are suitable for a trial of scar Patients who are suitable for a trial of scar

should be told by their primary carer that should be told by their primary carer that elective CS and VBAC have risks and elective CS and VBAC have risks and benefits.benefits.

They should:They should:• Read on the subject – RCOG 2008Read on the subject – RCOG 2008

• Discuss it with an obstetricianDiscuss it with an obstetrician

• Their decision will be respectedTheir decision will be respected

Patients planning VBAC require one to one Patients planning VBAC require one to one preparationpreparation

My guidelines for VBAC - 3 Any available record about the previous CS Any available record about the previous CS

is scrutinizedis scrutinized The patient is provided with individualised The patient is provided with individualised

chance of success with VBAC & maternal chance of success with VBAC & maternal and fetal risksand fetal risks

Delivery in a place capable of emergency Delivery in a place capable of emergency laparotomy is recommendedlaparotomy is recommended

Any limitation in the patient’s chosen place Any limitation in the patient’s chosen place of birth is discussedof birth is discussed

The discussion is documentedThe discussion is documented

My guidelines for VBAC - 4 Offer IOL by sweep membranes, ARM and Offer IOL by sweep membranes, ARM and

oxytocin in safe working hours at 39 – 41woxytocin in safe working hours at 39 – 41w Cervical ripening with Foley but not PGsCervical ripening with Foley but not PGs If admitted in spontaneous labour then If admitted in spontaneous labour then

review by obstetrician within 2 hrs is review by obstetrician within 2 hrs is desirabledesirable

IV line, group and saveIV line, group and save Epidural if required.Epidural if required. Monitor by continuous CTG only if Monitor by continuous CTG only if

oxytocin or epidural is in useoxytocin or epidural is in use

My guidelines for VBAC - 5 CS is recommended if there is failure to CS is recommended if there is failure to

progress i.e.progress i.e. <1 cm per hour dilatation over >4 hrs and >3 cm <1 cm per hour dilatation over >4 hrs and >3 cm

and good uterine activityand good uterine activity No head descent with >60 minutes active pushing in No head descent with >60 minutes active pushing in

the 2the 2ndnd stage stage Assisted delivery may be attempted according to Assisted delivery may be attempted according to

usual obstetric dictatesusual obstetric dictates

OR “Fetal Distress” i.e.OR “Fetal Distress” i.e. Scalp lactate >4.8 or CTG so abnormal as to warrant Scalp lactate >4.8 or CTG so abnormal as to warrant

scalp sampling by RCOG guidelinesscalp sampling by RCOG guidelines

My experience with VBAC - 1

330 private multigravid patients 2001 – 04330 private multigravid patients 2001 – 04 65 had undergone previous CS (20%)65 had undergone previous CS (20%) 32 attempted VBAC (50%)32 attempted VBAC (50%) 21were successful (66%)21were successful (66%) 12 by SVD and 9 assisted12 by SVD and 9 assisted

My experience with VBAC - 2 Among the 32 VBACs there were:Among the 32 VBACs there were:

2 patients who had 2 previous CS (one with a “thin lower 2 patients who had 2 previous CS (one with a “thin lower segment”)segment”)

5 patients whose previous CS was for failure to progress 5 patients whose previous CS was for failure to progress and 2 of these had a bigger baby during VBACand 2 of these had a bigger baby during VBAC

1 patient who had a third degree tear in her first SVD, 1 patient who had a third degree tear in her first SVD, elective CS for the second and SVD with an intact elective CS for the second and SVD with an intact perineum during VBACperineum during VBAC

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