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Interventions for supporting pregnant women's decision-making about mode of birth after a caesarean

  1. Dell Horey1,*,
  2. Michelle Kealy2,
  3. Mary-Ann Davey2,
  4. Rhonda Small2,
  5. Caroline A Crowther3

Editorial Group: Cochrane Pregnancy and Childbirth Group

Published Online: 30 JUL 2013

Assessed as up-to-date: 22 JUL 2013

DOI: 10.1002/14651858.CD010041.pub2


How to Cite

Horey D, Kealy M, Davey MA, Small R, Crowther CA. Interventions for supporting pregnant women's decision-making about mode of birth after a caesarean. Cochrane Database of Systematic Reviews 2013, Issue 7. Art. No.: CD010041. DOI: 10.1002/14651858.CD010041.pub2.

Author Information

  1. 1

    La Trobe University, Faculty of Health Sciences, Bundoora, VIC, Australia

  2. 2

    La Trobe University, Mother and Child Health Research, Melbourne, Victoria, Australia

  3. 3

    The University of Adelaide, ARCH: Australian Research Centre for Health of Women and Babies, The Robinson Institute, Discipline of Obstetrics and Gynaecology, Adelaide, South Australia, Australia

*Dell Horey, Faculty of Health Sciences, La Trobe University, Bundoora, VIC, 3086, Australia. d.horey@latrobe.edu.au.

Publication History

  1. Publication Status: Edited (no change to conclusions)
  2. Published Online: 30 JUL 2013

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Characteristics of included studies [ordered by study ID]
DiAMOND 2007

MethodsRandomised controlled trial (May 2004-Aug 2006).

Setting: 4 maternity units in south west England and Scotland.

Aim: to determine the effects of 2 computer-based decision aids on decisional conflict and mode of delivery among pregnant women who had a previous caesarean section.


Participants742 pregnant women with 1 previous lower segment caesarean section and delivery expected at ≥ 37 weeks were randomised. Women of all parities with no current obstetric problems were included but the most recent delivery must have been a caesarean section. Non-English speakers were excluded.

713 women were included in the primary analysis (96% of those randomised, 247 usual care; 250 information program and website; 245 decision analysis program). (Data missing for 2 participants).

13 participants were ineligible after randomisation and 14 withdrew.

Overall mean (SD) age at randomisation was 32.6 (4.7) years.

Women who consented to participate were slightly older (32.5 v 31.9 years, P = 0.05) and less deprived (P = 0.02) than those who did not take part.

Mean gestational age was 19.0 (4.4) weeks.


Interventions2 computer-based decision aids were delivered via a laptop computer after brief instructions from a researcher.

1) Information programme: women navigated through descriptions and probabilities of clinical outcomes for mother and baby associated with planned vaginal birth, elective caesarean section, and emergency caesarean section.

Aim: informational component: outcomes associated with planned vaginal delivery, elective caesarean section, and emergency caesarean section, including descriptions of possible health outcomes for both mother and baby.

Deliberative component: none described.

Other components: probabilities of having and not having the event, in both numerical and pictorial format.

Type: independent.

2) Decision analysis: mode of birth was recommended based on utility assessments performed by the woman combined with probabilities of clinical outcomes within a concealed decision tree.

Aim: to produce a computer printout of the outcome of a decision analysis with encouragement for discussion with midwife or obstetrician at subsequent antenatal visits.

Informational component: the outcomes associated with planned vaginal delivery, elective caesarean section, and emergency caesarean section. This comprised descriptions, but not explicit probabilities, of outcomes for both mother and baby.

Deliberative component: participants were asked to consider the value they attached to possible outcomes by rating each on a visual analogue scale from 0 to 100.
Ratings were not strictly equivalent to utility values, but considered to be a pragmatic method of assessment. These values were combined with the probabilities of each outcome in a decision tree to produce a recommended “preferred option” based on maximised expected utility.

Other components: none described.

Type: independent.

Control group: usual care - standard care given by obstetric and midwifery staff.


Outcomes2 primary outcomes

Decisional conflict score (37 weeks) using Decisional Conflict Scale. Data not collected postpartum.

Actual mode of birth (vaginal birth v caesarean delivery) from hospital records.

8 secondary outcomes

Anxiety 6-item short-form of the state scale of the Spielberger state-trait anxiety inventory (STAI).
Knowledge instrument not described.

5 subscales of the decisional conflict scale

Satisfaction with the decision (6 weeks post delivery) using satisfaction with decision scale.

Other outcomes (collected as longitudinal observational data during randomised controlled trial reported in Emmett 2010).

Mode of birth preference (baseline [approx. 19 weeks' gestation] and 37 weeks).


NotesInformed consent: YES.

Ethical approval: YES.

Funding source (amounts): BUPA Foundation. First author partly supported by a postdoctoral fellowship from the UK Department of Health National Coordinating Centre for Research Capacity Development. (no amounts reported).

Consumer involvement: the content of the decision aids was derived from best practice protocols, extensive literature review (including systematic reviews) and from clinical experience of issues salient to women. The content was also discussed with pregnant women from the earliest stage and revised according to

their comments.

Intervention quality: no independent assessment reported.

Mode of birth decisions made: mode of delivery preference was determined by asking women to indicate their planned method of delivery from the following options: attempt trial of labour (vaginal birth); planned caesarean section.


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskRandomisation sequence generated by computer.

Allocation concealment (selection bias)Low riskStudy reports "another member of staff with no other involvement in the trial performed the allocation" allocated the randomisation sequence, which had been computer-generated by a member of the study team.

Incomplete outcome data (attrition bias)
All outcomes
Low riskReasons for missing outcome data unlikely to be related to true outcome. Missing outcome data balanced in numbers across intervention groups, with similar reasons for missing data across groups.

Selective reporting (reporting bias)Low riskThe study protocol is available and all of the study’s pre-specified (primary and secondary) outcomes that are of interest in the review have been reported in the pre-specified way.

Other biasLow riskThe study appears to be free of other sources of bias.

Blinding of participants and personnel (performance bias)
All outcomes
Low riskNo blinding or incomplete blinding, but the review authors judge that the outcome is not likely to be influenced by lack of blinding.

Blinding of outcome assessment (detection bias)
All outcomes
Low riskNo blinding of outcome assessment, but the review authors judge that the outcome measurement is not likely to be influenced by lack of blinding.

Fraser 1997

MethodsRandomised controlled trial (April 1992 to November 1994).

Setting: 12 hospitals in North America (11 in Canada and 1 in USA).

Aim: to assess whether, for women who had a previous caesarean section, a prenatal education and support program promoting VBAC delivery increases the probability of vaginal delivery.


Participants1301 women were randomised; of these 1 ineligible woman was randomised in error, 6 miscarried, 3 therapeutic abortions, 2 delivered prior to 24 weeks' gestation, 13 lost to follow-up, and 1 withdrew because of language difficulties. Outcomes were also reported for 1280 infants.

1275 women (98%) were included in the primary analysis including 372 women with low motivation for VBAC (29%) and 903 with high motivation for VBAC (71%).

1135 women completed postpartum questionnaire (87% of those randomised and 89% of those in primary analysis).

Women were eligible if they had a single previous low transverse caesarean were less than 28 weeks' gestation, planned to deliver in participating hospital, received prenatal care from physician associated with participating hospital, and had sufficient English or French to complete questionnaire.

Women were ineligible if they had a previous VBAC section, a classic caesarean section or myomectomy scar, or a known multiple gestation.

Mean age of both groups was 31 +/-0.5 years.


InterventionsVerbal group: offered a prenatal education and support program provided by a research nurse with experience in prenatal instruction and a resource person with personal experience of VBAC and communication skills. There were 2 contacts. The first with the research nurse on day of randomisation and the second with both nurse and resource person 4 to 8 weeks later.

Aim: to apply the principles of the model of Green and Kreuter of health promotion-disease prevention interventions in the promotion of VBAC delivery to increase the probability of vaginal delivery.

Informational component: women were given a pamphlet emphasizing the benefits of VBAC section (given to the control group), informed of consensus panel recommendations favouring planned vaginal birth and the probability of success of an attempt for vaginal birth in her centre, and reassured about pain relief options for labour.
Women considering tubal sterilization were counselled on alternative methods of permanent contraception, including vasectomy for their partner.

Deliberative component: at first contact motivation to attempt VBAC was assessed and as were the woman's perceptions of the attitudes of key persons in her social network, including her spouse and her treating obstetrician.
Other components: the resource person participated in the second contact to provide peer influence and support. Attempts were made to identify and discuss perceived barriers to VBAC including, when applicable, the views of the treating obstetrician. As much as possible, the intervention was individualised to the woman's needs.

Type: shared/mediated.

Control or document group: provided with a pamphlet detailing the benefits of planned VBAC delivery.


OutcomesMotivation to attempt vaginal birth after a previous caesarean delivery was self assessed and measured on a 10 cm visual analogue scale: stratum I, low motivation; stratum II, high motivation.

Proportion of women achieving vaginal delivery.

Proportion of women attempting vaginal delivery (defined with at least 1 of the following criteria: (1) a vaginal delivery, (2) a caesarean section that was preceded by at least 4 hours of labour in the hospital, (3) a caesarean section preceded by in-hospital labour of less than 4 hours but where there was an urgent indication for abdominal delivery).

Sense of control over the birth experience measured with the Birth Experience Rating Scale (shortened version of Labor Agentry Scale adapted for study) 12 and 72 hours postpartum (all women after 24 weeks of pregnancy). 18-item Lickert-type each with seven steps and maximum score of 126.

Participants were also asked about the effects of study participation on the ease of their decision on mode of birth.

Adverse outcomes were reported for mothers and neonates.


NotesInformed consent: YES.

Ethical approval: YES.

Funding source (amounts): supported by operating grant No. MT 11430 from the Medical Research Council of Canada and by nominal awards (first author from the Medical Research Council of Canada, grant No DG-401; E.M. from the National Health Research and Development Program, National Health Research Scholar, No. 6605-2487-47) (no amounts reported).

Consumer involvement: the resource person had personal experience of VBAC but no other consumer involvement in the study design or conducted was reported.

Intervention quality: no independent assessment reported.

Mode of birth decisions made: mode of delivery preference using a 10 cm visual analogue scale to indicate agreement or disagreement with the statement "I plan to attempt a vaginal delivery in this pregnancy". Participants were also asked whether participation in the study influenced the ease of decision-making (a higher proportion of women in the document group indicated that the study had no effect [67% v 38%]).


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Unclear riskUnclear how the random sequence was generated.

Allocation concealment (selection bias)Low risk"Randomization, which was performed through a centralized telephone answering service, was blocked and stratified by hospital and by the woman's motivation to attempt vaginal delivery".

Incomplete outcome data (attrition bias)
All outcomes
Low riskAll data satisfactorily reported.

Selective reporting (reporting bias)Low riskInsufficient information to assess whether an important risk of bias exists.

Other biasLow riskThe study appears to be free of other sources of bias.

Blinding of participants and personnel (performance bias)
All outcomes
Low riskNo blinding of mode of birth, but the review authors judge that this outcome measurement is not likely to be influenced by lack of blinding.

Blinding of outcome assessment (detection bias)
All outcomes
Low riskNo blinding of mode of birth, but the review authors judge that this outcome measurement is not likely to be influenced by lack of blinding.

Shorten 2005

MethodsRandomised controlled trial (May 2001 and May 2003).

Setting: 3 hospital prenatal clinics and 3 obstetric practices in New South Wales, Australia.

Aim: to determine whether a decision aid for women who have experienced previous caesarean birth facilitates informed decision-making about birth options during a subsequent pregnancy.


Participants227 women who had 1 previous caesarean section were randomised (intervention group = 115 and control group = 112). Women were recruited when less than 20 weeks' gestation. Women who had experienced more than 1 previous caesarean section, classical or unknown uterine scar, a history of uterine rupture or upper segment perforation, multiple pregnancy, or obstetric or medical contraindications to vaginal birth and/or trial of vaginal birth (e.g. placenta previa) in the current pregnancy were excluded.

193 women completed the survey at 36 weeks (intervention group = 99 and control group = 94).

There was no significant difference in the mean age of the groups (control = 31.5 years and intervention = 32.05 years).

Women in the intervention group were significantly more likely to report problems after their previous caesarean (33.0% cf 46.1%, P = 0.05).


InterventionsDecision-aid booklet constructed using the Ottawa Decision Framework as a format and incorporating evidence-based information, explicit probability illustrations, and values clarification exercises.

Type: independent.

Aim: to facilitate ‘quality’ decision-making based on research evidence about the risks and benefits of a trial of vaginal birth versus elective caesarean section weighted against individual values and needs (Shorten 2004).

Informational component: risks and benefits of trial of labour versus elective repeat caesarean were presented. Major advantages of trial of vaginal birth over elective caesarean included: good success rates for attempted VBAC (60% to 80%), shorter hospital stay and recovery time, greater opportunities to establish breastfeeding and avoidance of risks related to surgery. Disadvantages included potential for complications such as rupture of uterine scar, possible instrumental vaginal birth (forceps/vacuum), vaginal trauma and emergency caesarean. Major advantages of elective caesarean included the ability to plan or book in advance therefore reducing uncertainty or labour fears, and reduction in risks associated with emergency caesarean. Disadvantages included surgical risks such as infection, anaesthetic problems, bleeding, blood clots (lung and legs) and longer postnatal recovery time, as well as increased likelihood of transient tachypnoea of the newborn.

Deliberative component: a values clarification exercise to guide women through a summary of major pros and cons, based on the discussion within the body of the booklet. This involved questions about the importance to them of particular issues a response scale (“not important”, “some/moderately important” and “very important”). The women were also to record any additional issues. A 15-point “Birth Preference Scale” was placed at the end of the exercise to elicit final birth preferences between trial of vaginal birth and elective caesarean birth.

Other components: explicit probability illustrations.

Control group: received routine pregnancy care..


OutcomesBirth preference (12-18 weeks; 28 weeks; 36 weeks).

Knowledge score (28 weeks, 36 weeks) assessed with 15-item questionnaire developed and piloted for the study based on key risk and benefit information contained in the decision aid.

Decisional conflict score (28 weeks, 36 weeks) using Decisional Conflict Scale.

Mode of birth from hospital medical records.

Satisfaction (6-8 weeks postnatal) using a visual analogue scale (0 to 10) where women were asked to indicate ‘‘how they feel about their birth experience’’.


NotesInformed consent: YES.

Ethical approval: YES.

Funding source (amounts): MBF Research Grant, Sydney; The University of Wollongong New Researcher Grant Scheme, Wollongong; NSW Midwives Association Research Scholarship, Sydney, New South Wales, Australia (no amounts reported).

Consumer involvement: a critical review of the draft decision aid included two women who had already experienced caesarean birth (Reported in Shorten 2004).

Intervention quality: the International Patient Decision Aid Standards (IPDAS) Collaboration assessment of this decision aid indicates that it meets:

14/14 of the content criteria; 8/9 of the development process criteria and 2/2 of the effectiveness criteria.

Mode of birth decisions made: mode of delivery preference using a 15-point Birth Preference Scale (at baseline, 28 weeks and 36 weeks).


Risk of bias

BiasAuthors' judgementSupport for judgement

Random sequence generation (selection bias)Low riskParticipant code numbers were prepared by computer-based randomised generation.

Allocation concealment (selection bias)Low riskAfter recruitment and consent were obtained, a code number was assigned to each participant and an opaque envelope with corresponding number opened and allocation recorded.

Incomplete outcome data (attrition bias)
All outcomes
Low riskMissing outcome data balanced in numbers across intervention groups for main study outcome (preferred mode of birth) with similar reasons for missing data across groups; 16 women were lost to follow-up from the intervention group (14%) and 18 from the control group (16%) by survey 3 at 36 weeks.

Selective reporting (reporting bias)Low riskThe study protocol is available. All the study’s pre-specified (primary and secondary) outcomes have been reported and additional information has been provided by the author.

Other biasLow riskThe study appears to be free of other sources of bias.

Blinding of participants and personnel (performance bias)
All outcomes
Low riskParticipants blinded to their allocation, although they all expected to receive information about birth options during the pregnancy. Midwives and doctors were blinded to both women’s enrolment and study allocation. However, women who used the decision aid as specified and in a process of consultation with their midwife or doctor would have negated the blinding of their clinicians, and perhaps of the women themselves. However authors judge that the outcome is not likely to be influenced by lack of blinding.

Blinding of outcome assessment (detection bias)
All outcomes
Low riskNo blinding or incomplete blinding, but the review authors judge that the outcome is not likely to be influenced by lack of blinding.

 
Characteristics of excluded studies [ordered by study ID]

StudyReason for exclusion

Eden 2009Hypothetical decision. Participants were not pregnant.

Flamm 1997Intervention does not aim to support decision about mode of birth.

Greene 1989Participants did not necessarily have previous caesarean and information about previous deliveries not reported.

 
Characteristics of ongoing studies [ordered by study ID]
Begley 2013

Trial name or titleImproving the organisation of maternal health service delivery, and optimising childbirth, by increasing vaginal birth after caesarean section (VBAC) through enhanced women-centred care (OptiBIRTH)

MethodsA randomised trial

Participants1. Pregnant women aged over 18 years
2. Who have had one previous caesarean section
3. Who speak a language for which translation is available
4. Who give their consent

Interventions1. Evidence-based education of women and clinicians, introduction of communities of practice (women and clinicians sharing knowledge), opinion leaders, audit and peer review of caesarean sections in each hospital, and joint decision-making by women and clinicians. The content and details of the intervention will be determined through systematic reviews and qualitative research.
2. Usual care.

OutcomesPrimary outcome measures

Change from baseline in each hospital in the proportion of women who have had one previous caesarean section who have a vaginal birth during the study.

Secondary outcome measures

1. Gestational age at birth
2. Length of labour
3. Emotional well-being, feelings of anxiety, control, satisfaction with care and perception of involvement in care, during pregnancy and the postnatal period.
4. Intrapartum interventions (induction or augmentation of labour, use of epidural and fetal monitoring, mode of birth).
5. Maternal morbidities during pregnancy and the postnatal period (for example, pain, postpartum haemorrhage, wound infection, abdominal pain, depression).
6. Neonatal morbidities (resuscitation, Apgar scores, admission to intensive care).
7. Breastfeeding.
8. Length of hospital stay (mother and infant).
9. Readmission.

Starting date01/12/2013

Contact informationProf Cecily Begley

School of Nursing and Midwifery
Trinity College Dublin
City/town Dublin
Zip/Postcode D2
Country Ireland
Tel +353 (0)1 8962693
Fax +353 (0)1 8963001
Email cbegley@tcd.ie

Notes

Wise 2011

Trial name or titleThe effect of an antenatal decision aid booklet on rate of vaginal birth after caesarean (VBAC) in women with previous caesarean section.

MethodsRandomised controlled trial.

ParticipantsPregnant women with 1 previous caesarean section who are less than 25 weeks' gestation in current pregnancy at recruitment.

InterventionsThe decision aid is a comprehensive 25-page booklet that first explains the risks and benefits of elective repeat caesarean and of VBAC, and then asks the woman to write down her own values and preferences about the 2 birth options. It will be administered at the time of the consultation in the Positive Birth After Caesarean (PBAC) Clinic.

The patient pamphlet is 6 pages and briefly lists risks and benefits of elective repeat caesarean and of VBAC. It is administered at the time of the consultation in PBAC clinic.

OutcomesThe rate of vaginal birth after caesarean is determined using the perinatal database at the hospital. 

Mean decisional conflict score about birth choice, out of 5 measured just prior to intervention, and again at 33-35 weeks' gestation. 

Mean knowledge score about birth choices, out of 15 measured just prior to intervention, and again at 33-35 weeks' gestation. 

Starting date1/11/2011.

Contact informationDr Michelle Wise

Department of Obstetrics and Gynaecology

Faculty of Medical and Health Sciences

University of Auckland

Private Bag 92019

Auckland 1142

NotesTarget sample 314.

 
Comparison 1. Decision support intervention versus usual care

Outcome or subgroup titleNo. of studiesNo. of participantsStatistical methodEffect size

 1 Planned mode of birth: VBAC32071Risk Ratio (M-H, Fixed, 95% CI)1.03 [0.97, 1.10]

 2 Planned mode of birth: caesarean birth32071Risk Ratio (M-H, Fixed, 95% CI)0.96 [0.84, 1.10]

 3 Planned mode of birth: unsure versus sure32071Risk Ratio (M-H, Fixed, 95% CI)0.87 [0.62, 1.20]

 4 Permanent adverse outcome12555Risk Ratio (M-H, Fixed, 95% CI)0.66 [0.32, 1.36]

 5 Severe adverse outcome12555Risk Ratio (M-H, Fixed, 95% CI)1.02 [0.77, 1.36]

 6 Unclear impact adverse outcome12555Risk Ratio (M-H, Fixed, 95% CI)0.66 [0.27, 1.61]

 7 Congruence - preferred and actual31921Risk Ratio (M-H, Fixed, 95% CI)1.02 [0.96, 1.07]

 8 Actual mode of birth (VBAC)32190Risk Ratio (M-H, Random, 95% CI)0.97 [0.89, 1.06]

    8.1 Independent decision support
2915Risk Ratio (M-H, Random, 95% CI)1.01 [0.88, 1.15]

    8.2 Mediated decision support
11275Risk Ratio (M-H, Random, 95% CI)0.92 [0.82, 1.03]

 9 Decisional conflict at 36-37 weeks2787Std. Mean Difference (IV, Random, 95% CI)-0.25 [-0.47, -0.02]

 10 Decisional conflict - change between 28 and 36 weeks1187Mean Difference (IV, Fixed, 95% CI)-0.32 [-1.02, 0.38]

 11 Knowledge2787Std. Mean Difference (IV, Random, 95% CI)0.74 [0.46, 1.03]

 12 Satisfaction with decision-making process2797Std. Mean Difference (IV, Fixed, 95% CI)0.06 [-0.09, 0.20]

 13 Maternal morbidity11275Risk Ratio (M-H, Fixed, 95% CI)0.90 [0.38, 2.10]

 14 Uterine rupture11275Risk Ratio (M-H, Fixed, 95% CI)1.32 [0.46, 3.78]

 15 Hysterectomy11275Risk Ratio (M-H, Fixed, 95% CI)0.20 [0.01, 4.11]

 16 Blood transfusion11275Risk Ratio (M-H, Fixed, 95% CI)0.66 [0.11, 3.93]

 17 All adverse neonatal indicators11280Risk Ratio (M-H, Fixed, 95% CI)0.93 [0.71, 1.21]

 18 Perinatal deaths11280Risk Ratio (M-H, Fixed, 95% CI)0.50 [0.09, 2.69]

 19 Apgar score < 7 at 5 minutes11280Risk Ratio (M-H, Fixed, 95% CI)0.66 [0.24, 1.84]

 20 Admission to NICU11280Risk Ratio (M-H, Fixed, 95% CI)1.00 [0.75, 1.34]

 
Summary of findings for the main comparison.

Decision support intervention compared with usual care for women making decisions about mode of birth in a pregnancy after caesarean birth

Patient or population: women deciding about mode of birth in a pregnancy after caesarean birth

Settings: all settings

Intervention: decision support intervention

Comparison: usual care

OutcomesIllustrative comparative risks* (95% CI)Relative effect
(95% CI)
No of Participants
(studies)
Quality of the evidence
(GRADE)
Comments

Assumed riskCorresponding risk

Usual careDecision support intervention

Planned or preferred mode of birth: VBAC57% to 65%67% (63 to 71%)RR 1.03 (0.97 to 1.10)2071
(3 studies)
⊕⊕⊕⊕
high

Planned mode of birth: unsure69-74 per 100065 per 1000 (46 to 89)RR 0.87 (0.62 to 1.20)2071
(3 studies)
⊕⊕⊕⊕
high

Adverse outcomes1 Permanent2⊕⊕⊕⊝
moderate5



14 per 10009 per 1000RR 0.66 (0.32 to 1.36)2555
(1 study)

Severe3



68 per 100070 per 1000RR 1.02 (0.77 to 1.36)2555
(1 study)

Unclear4

9 per 10006 per 1000RR 0.66 (0.27 to 1.61)2555
(1 study)

Congruence between preferred and actual mode of birth75%75% (67% to 78%)RR 1.02 (0.96 to 1.07)1921

(3 studies)
⊕⊕⊕⊕
high

Actual mode of birth (VBAC versus caesarean)30% to 42%45% (41% to 50%)RR 0.97 (0.89 to 1.06)2190
(3 studies)
⊕⊕⊕⊕
high

*The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI).
CI: Confidence interval; RR: Risk Ratio; VBAC: vaginal birth after caesarean

1 Adverse outcomes for both infants (1271) and mothers (1275) were categorised as follows:

  • Permanent: where there is an ongoing adverse impact;
  • Severe: where there has been risk of death and significant costs in terms of time, emotional distress and resources
  • Major: where there has been no risk of death but significant costs in terms of time, emotional distress and resources
  • Non-major: no risk of death and minor costs
  • Unclear: where impact is unable to be determined from data available


2 Permanent adverse outcomes included perinatal death and hysterectomy

3 Severe adverse outcomes included uterine rupture or dehiscence and admission to Neonatal Intensive Care Unit (NICU)

4 Unclear adverse outcomes included maternal blood transfusion and 5-minute Apgar score < 7

5 Only one study provided data

GRADE Working Group grades of evidence
High quality: Further research is very unlikely to change our confidence in the estimate of effect.
Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate.
Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate.
Very low quality: We are very uncertain about the estimate.


 
Table 1. Categorisation of adverse effects

CategoryDefinitionOutcomes included

PermanentOngoing adverse impactMothers

Hysterectomy

Infants

Perinatal death

SevereRisk of death and significant costs in terms of time, emotional distress and resourcesMothers

Uterine rupture or dehiscence

Infants

Admission to NICU

MajorNo risk of death but significant costs in terms of time, emotional distress and resourcesNot applicable

Non-majorNo risk of death and minor costsNot applicable

UnclearImpact unable to be determined from available dataMothers

Blood transfusion

Infants

Apgar score < 7 at 5 minutes

 NICU: neonatal intensive care unit
 
Table 2. Other systematic reviews

Review nameObjectiveApproachNumber of trials [Names of VBAC trials included]Outcomes (*Common to this review)*Results

Dugas 2012To evaluate the effectiveness of different DA tools on knowledge, anxiety, decisional conflict, final choice and final outcome, in the specific context of pregnancy and birth.Systematic review with meta-analysis where possible comparing different decision aid formats, e.g. computer-based information program, individual counselling, group counselling, decision analysis tool or decision tree.

Does not report by decision (e.g. VBAC)
10 RCTs

[DiAMOND 2007; Shorten 2005]
  • Knowledge*
  • Anxiety
  • Decisional conflict*
  • Final choice*
  • Final outcome*
No meta-analysis performed for knowledge due to heterogeneity

Decisional conflict decreased for DAs based on computer-based information programs or decisional analysis tools.

No significant influence on final choice.

Final outcomes only influenced by DAs based on decisional analysis tools.

Khunpradit 2011To evaluate the effectiveness and safety of non-clinical interventions for reducing unnecessary caesarean sections.Cochrane Systematic Review

Reports by intervention type including decision aids and prenatal education and support
16 studies including 5 cluster-RCTs, 6 RCTs and 5 interrupted time series

[DiAMOND 2007; Fraser 1997; Shorten 2005]
Primary outcomes

  • Rate of caesarean section*
  • Rate of unnecessary caesarean section


Secondary outcomes

  • Maternal and fetal or neonatal complications such as maternal and neonatal mortality*, postpartum anaemia*, postpartum infection*, birth asphyxia* and admission to neonatal intensive care unit*
  • Costs and financial benefits noted from the change in procedure rates
  • Patient* and provider satisfaction
Reports DAs and prenatal education and support separately.

No difference in caesarean birth rates

No difference in VBAC/ caesarean birth rates or adverse events. Geater satisfaction with DAs but effect small.

Say 2011To evaluate the effects of
patient DAs designed for pregnant women on clinical and psychosocial outcomes.
Systematic review with no meta-analysis due to heterogeneity of outcomes in primary studies and small number of studies.

Studies reported by decision to be made, including VBAC
11 RCTs

[DiAMOND 2007; Shorten 2005]
Reports selected outcomes from included studiesBoth DAs improved knowledge and decreased
decisional conflict but neither influenced mode of delivery.

Stacey 2011To evaluate the effectiveness of DAs for people facing treatment or screening decisions.Cochrane Systematic Review

Reports by attributes of the decision and the decision-making process. Also reports results for DAs associated with childbirth procedures (VBAC, external cephalic version for women with breech presentation)
86 RCTs

[DiAMOND 2007; Shorten 2005]
Primary outcomes

  • Decision attributes - knowledge*, accurate risk perceptions, and value congruence with chosen option
  • Decision-making process attributes - recognise decision needs to be made; know options;understand values affect decisions; be clear about option features that matter most; discuss values with practitioner; and become involved in preferred ways..


Secondary outcomes

  • Behavioral, health, and health system effects.(Decisional conflict*; Patient-practitioner communicationParticipation in decision-making; Proportion undecided*; Satisfaction*)
Overall increase in knowledge and decrease in decisional conflict.

No difference in preference for (Shorten 2005) or actual vaginal mode of delivery
(Montgomery 2007) following previous caesarean section.

Viemmix 2012To determine the effectiveness of DAs to improve informed decision-making in pregnancy care.Systematic review with meta-analysis for global assessment (not by actual decision).10 RCTs

[DiAMOND 2007; Shorten 2005]
Primary outcomes

  • Knowledge*
  • Decreased decisional conflict scores*
  • Decreased anxiety


Secondary outcomes

  • Effectiveness of DA (proportion of individuals undecided*, accuracy of risk perception of treatment options, enough information to make decision, involvement in decision-making, regret of choice* and satisfaction with choice*)
  • Acceptability of DA (readability and usefulness of information to make choice)
  • Decision behaviour outcomes (outcome of decision*, uptake of intervention, and adherence to chosen option)
  • Health outcomes (neonatal and maternal morbidity and mortality*, Apgar score*, gestational age at delivery, and depression and self-esteem); and
  • Healthcare system outcomes (cost-effectiveness of DA, length of staying hospital and length of consultation)
Knowledge increased (WMD 11.06, 95% CI 4.85, 17.27),

Decreased decisional conflict scores (WMD 3.66, 95% CI 6.65, 0.68)

 CI: confidence interval
DA: decision aid
RCT: randomised controlled trial
VBAC: vaginal birth after caesarean
WMD: weighted mean difference