REVIEW URRENT C OPINION
Planned caesarean section or trial of vaginal delivery? A meta-analysis Sultana Azam a, Amina Khanam a, Seema Tirlapur b, and Khalid Khan b,c
Purpose of review This systematic review with meta-analysis aims to determine whether maternal outcomes are better with antenatal choice to give birth by caesarean section compared to vaginal birth, in singleton pregnancies in low-risk women without a subsequent pregnancy. The main outcome measures used were as follows: postpartum haemorrhage, postnatal depression, urinary incontinence and maternal mortality. Recent findings There were seven relevant studies (2 730 410 women) that were of high quality, identified for the purpose of this review. Randomized and observational evidence was synthesized, showing no real difference in maternal morbidity risk: maternal mortality (relative risk 0.19, 95% confidence interval 0.0013–27.27, P ¼ 0.51); postpartum haemorrhage (relative risk 1.15, 95% confidence interval 0.40–3.31, P ¼ 0.79) and blood transfusion (relative risk 0.91, 95% confidence interval 0.39–2.13, P ¼ 0.84). Summary On the basis of the current research and the findings of this review, planned caesarean section is associated with a lower risk of developing urinary incontinence symptoms postpartum or having a blood transfusion yet conversely results showed an increased risk of postpartum haemorrhage. The synthesized data are not applicable to clinical practice; however, they prompt much further investigation into planned delivery and its associated morbidity risk. Keywords caesarean section, maternal morbidity, systematic review, vaginal delivery
INTRODUCTION Caesarean section rates have increased worldwide [1,2]. Women are exhibiting preference for caesarean section [3], and consequently caesarean section is increasingly being carried out on demand. Health professionals’ willingness to accept a caesarean section request in the absence of medical indication is increasing [4–7]. Initially, caesarean section was introduced as a life-saving intervention and in that respect, it still remains undisputedly important; however, it is evident that caesarean section has become an increasingly on-demand procedure [8]. Is this increase reasonable and are maternal choice and professional advice fully informed? The safety of vaginal birth is propagated largely using data on successful vaginal births, excluding emergency caesarean section that occurs in labour. Emergency caesarean section is associated with higher rates of complications [9]. At the onset of labour, it is unknown whether vaginal birth will be achieved or not. Thus, the risks inherent in emergency caesarean section should be attributed to vaginal birth
when counselling about antenatal choices. There is a lack of appropriate evidence syntheses in this area [10]. This review aims to compare maternal outcomes associated with antenatal planned mode of delivery, either caesarean section or vaginal birth, in low-risk women with singleton pregnancy.
METHODS This systematic review was conducted prospectively deploying a protocol based on contemporary methods and reported in accordance with the
a
Barts and The London Medical School, bWomen’s Health Research Unit, Queen Mary University of London and cBarts Health NHS Trust, The Royal London Hospital, London, United Kingdom Correspondence to Sultana Azam, Barts and The London Medical School, Garrod Building, Turner Street, Whitechapel, London E1 2AD, UK. E-mail:
[email protected] Curr Opin Obstet Gynecol 2014, 26:461–468 DOI:10.1097/GCO.0000000000000114
1040-872X ß 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins
www.co-obgyn.com
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Women’s health
KEY POINTS Women are increasingly influencing clinical decisions when it comes to preferred planned delivery. Little evidence is available to help women make informed decisions regarding planned delivery. The existing evidence may be misleading because of inaccurate methodological application and analysis. More research into maternal outcomes in relation to planned delivery in low-risk women is needed.
Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement [11].
DATA SOURCES A search for the following sources was performed from database inception until January 2013: Medline, Embase, PubMed, Cumulative Index to Nursing and Allied Health Literature and the Cochrane Library. Hand searches of bibliographies from retrieved primary articles were also performed. No time or language restrictions were imposed. We used Medical Subject Headings, keywords and word variants for women, pregnancy, mode of delivery and caesarean in the search strategy. The searches were updated in November 2013.
SELECTION OF STUDIES Cohort studies were included if their participants were low-risk women in their first pregnancy, who planned antenatally to deliver by caesarean section or vaginal birth and whose outcomes were grouped by antenatal intention to have caesarean section or vaginal birth (rather than by actual mode of delivery) and whose follow-up ensured removal of the influence of subsequent pregnancies on outcomes. After inception, the cohort was followed up recording the actual mode of delivery and maternal outcomes before the next pregnancy. The results were grouped by intention to give birth by caesarean section or vaginal birth. Excluded were studies that recruited women with caesarean section or vaginal birth and based their results on actual mode of delivery.
DATA EXTRACTION AND STUDY QUALITY ASSESSMENT Two reviewers (S.A. and A.K.) independently performed data extraction and quality assessment. Any differences were resolved through discussion. The 462
www.co-obgyn.com
Newcastle–Ottawa Scale was used for assessing the methodological quality of observational studies [12] against predefined criteria for the selection process, comparability of the cohorts (confounding), and methods of outcome assessment (adequacy of follow-up). The risk of bias tool [13] was used to assess quality of included randomized control trials (RCTs). Quantitative data were extracted from text and tables, generating 22 tables of antenatally planned birth mode and outcomes, including maternal mortality, postpartum haemorrhage (PPH), blood transfusion, as a marker of PPH, postnatal depression (PND) and urinary incontinence, respectively.
DATA SYNTHESIS Relative risks (RR) and 95% confidence intervals (CI) for individual studies were plotted. Heterogeneity was assessed graphically with forest plots and statistically using chi-square test and the I2 value. Random effects model was used for meta-analyses when heterogeneity was observed. Funnel asymmetry was assessed to examine publication and related biases when there were sufficient studies.
RESULTS The search generated 13 983 citations. Seven studies, six nonrandomized [14,15 ,16,17 ,18 ,19] and one randomised [20], appeared relevant with outcomes being reported amongst 2 730 410 women (Fig. 1). Table 1 demonstrates the characteristics of each study included. Hannah et al. [20–22], the only RCT included, investigated breech deliveries for maternal outcomes in three publications. As shown by Fig. 2, quality was high in the six observational studies and one RCT included in the review. &
&
&
Randomized evidence The results from the Breech Trial by Hannah et al. [20] have been summarized. There was no difference in risk of PPH between the two groups (RR 0.77, 95% CI 0.34–1.75, P ¼ 0.53). There was no difference in risk of developing postnatal depression symptoms at 6 weeks (RR 6.94, 95% CI 0.36–134.2, P ¼ 0.2) [20], 3 months (RR 0.93, 95% CI 0.70–1.24, P ¼ 0.68) [21] and 2-year postpartum without any subsequent pregnancies (RR 0.90, 95% CI 0.62–1.30, P ¼ 0.60) [22]. A reduced risk of developing urinary incontinence symptoms was found at 3-month postpartum in the planned caesarean section group (RR 0.62, 95% CI 0.41–0.93, P ¼ 0.02) [21]; however, findings at 2-year postpartum in women with no subsequent Volume 26 Number 6 December 2014
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Planned caesarean section or vaginal delivery? Azam et al.
Total citations identified by electronic (n = 13 978) and hand searching (n = 5) (n = 13 983)
Removal of duplicate citations (n = 196)
Total citations reviewed by title (n = 13 787)
Citations excluded after screening titles and/or abstracts (n = 13 541)
Articles assessed in full text (n = 246)
Articles excluded (n = 239) because outcomes of interest not reported or not based on planned mode of delivery
Studies included in systematic review (n = 7) Outcomes Cohort RCT Maternal death n=2 n=1 Postpartum haemorrhage n=4 n=1 Blood transfusion n=5 n=1 Postnatal depression n=0 n=1 Urinary incontinence n=1 n=1
FIGURE 1. Flow chart of study identification. RCT, randomized controlled trial.
pregnancies during this period showed no difference (RR 0.81, 95% CI 0.63–1.06, P ¼ 0.14) [22]. Findings have shown no difference in risk of maternal mortality between the two groups (RR 1.24, 95% CI 0.79–1.95, P ¼ 0.35) [20].
graphically represent the meta-analysis results for PPH and blood transfusion and suggest an overall increase in risk with planned caesarean section; however, the results are not significant.
DISCUSSION Observational evidence As a result of the limited number of studies included in this review, combined RR were calculated for the outcomes of mortality (RR 0.19, 95% CI 0.0013– 27.27, P ¼ 0.51), PPH (RR 1.15, 95% CI 0.40–3.31, P ¼ 0.79) and blood transfusion (RR 0.91, 95% CI 0.39–2.13, P ¼ 0.84) (Table 2). Figures 3 and 4
We found that women who had a planned caesarean section were associated with lower morbidity, including avoidance of haemorrhage, PND and urinary incontinence compared to those with a planned vaginal birth. No evidence supported a protective role of an antenatal planned caesarean section with anal incontinence.
1040-872X ß 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins
www.co-obgyn.com
463
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Women’s health Table 1. Characteristics of included studies Total cohort number of participants
Study design
Author and year
Prospective cohort
Kor-Anantakul et al. (2008) [14]
1429
Larsson et al. (2011) [15 ]
541
Wesnes et al. (2009) [16]
12 679
&
Retrospective cohort
Geller et al. (2010) [17 ]
Follow-up period postpartum
Women delivering in southern Thailand.
Mortality (ICD); BT
1 week
Low-risk women from Stockholm, Sweden.
PPH (>1000 ml)
3 months
Low-risk women recruited from the Norwegian Mother and Child Cohort study.
UI (ICS)
6 months
&
4048
Low-risk women delivering in North Carolina, USA.
PPH (>500 ml); BT
Not specified
Holm et al. (2012) [18 ]
144 705
Low-risk women delivering in Denmark.
BT
1 week
Women who delivered in Canada’s acute-care hospitals.
Mortality (ICD-9); PPHa; BT
Not specified
Women chosen from the Term Breech Trial, with a singleton foetus in a frank or complete breech presentation.
Mortality; PPH (>1500 ml); BT; PND (score >12 EPDS); UI; AI
6 weeks, 3 months, 2 years
&
Liu et al. (2007) [19] Randomized controlled trial
Outcomes and their definitions
Participants’ characteristics
2 339 186
Hannah et al. (2000, 2002a) [20–22]
2083
a On the basis of follow-up from the same cohort. AI, anal incontinence; BT, blood transfusion; CS, caesarean section; EPDS, Edinburgh postnatal depression scale; ICD, International classification of disease; ICS, International Continence Society; PND, postnatal depression; PPH, postpartum haemorrhage; UI, urinary incontinence; VB, vaginal birth.
(a) Observational study included in the assessment
Quality assessment score based on criteria 0
1
2
3
4
5
6
7
8
9
Kor-Anantakul et al. (2008) [14] Larsson et al. (2011) [15*] Wesnes et al. (2009) [16] Geller et al. (2010) [17*] Holm et al. (2007) [18*] Liu et al. (2007) [19] Selection
Comparability
(b) Type of bias Random sequence generation Allocation concealment
Overall risk of bias Low
Description Centrally controlled computerized randomization
Low
Blinding
High
Random allocation accessed through a touch-tone telephone The nature of the intervention (i.e. planned CS), makes this impossible Data were collected for 2083 participants for outcomes mortality, PPH and PND Data were collected for 1596 out of 2083 participants for UI and PND Data were collected for 917 out of 2083 participants for UI and PND Outcomes of interest pre-specified and published were reported
Incomplete outcome data Low High High Selective reporting
Low
FIGURE 2. Quality assessment of included studies. (a) Observational studies using Newcastle–Ottawa score. (b) Risk of bias assessment for randomized controlled trial Hannah et al. [20]. CS, caesarean section; PND, postnatal depression; PPH, postpartum haemorrhage; UI, urinary incontinence. Reproduced from [20]. 464
www.co-obgyn.com
Volume 26 Number 6 December 2014
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Planned caesarean section or vaginal delivery? Azam et al. Table 2. Results from observational evidence and meta-analysis for outcomes Relative risk
Lower CI
Upper CI
P value
Combined meta-analysis
0.19
0.0013
27.27
0.5088
Kor-Anantakul et al. (2008) [14]
0.30
0.00
12.67
–
Liu et al. (2007) [19]
0.02
0.00
3.11
–
Combined meta-analysis
1.15
0.40
3.31
0.7899
8.30
2.43
28.26
Outcome
Study
Mortality
PPH
Kor-Anantakul et al. (2008) [14]
0.73
0.46
1.15
–
Geller et al. (2010) [17 ]
0.19
0.05
0.67
–
&
BT
–
Larsson et al. (2011) [15 ] &
Liu et al. (2007) [19]
1.58
0.89
2.80
–
Combined
0.91
0.39
2.13
0.8358
Kor-Anantakul et al. (2008) [14]
3.58
1.48
8.55
–
Larsson et al. (2011) [15 ]
0.71
0.27
1.86
–
Geller et al. (2010) [17 ] &
0.87
0.29
2.55
–
Holm et al. (2012) [18 ]
1.28
1.19
1.38
–
Liu et al. (2007) [19]
0.24
0.14
0.44
&
&
PND
–
–
UI
Wesnes et al. (2009) [16]
–
0.33
–
0.25
0.43
– – –
BT, blood transfusion; CI, confidence interval; PND, postnatal depression; PPH, postpartum haemorrhage; UI, urinary incontinence.
We complied with the PRISMA methodological and reporting standards [11]. Concerted efforts were made to identify all available evidence by searching multiple databases without language restrictions. When assessable, funnel asymmetry was not evident. The included studies vary in methodological features; however, the quality was generally good. Data on the number of women who achieved successful planned vaginal birth or successful planned caesarean section were obtained, showing
that 92% of deliveries were successful planned vaginal birth and 79% of deliveries were successful planned caesarean section. These data are misrepresentative of clinical reality most likely due to the largely varied definitions of preplanned vaginal birth and caesarean section throughout the studies, nevertheless taking into account the nature of the studies that can be expected. A limited number of studies included in the review impede the scope of statistical significance of findings, and although
Relative risk meta-analysis plot (random effects) Kor-Anantakul et al. (2008) [14]
8.30 (2.43, 28.26)
Larsson et al. (2011) [15*]
0.73 (0.46. 1.15)
Geller et al. (2010) [17*]
0.19 (0.05, 0.67)
Liu et al. (2007) [19]
1.58 (0.89, 2.80)
Combined [random]
1.15 (0.40, 3.31)
0.01
0.1 0.2 0.5
1
2
5
10
100
Relative risk (95% confidence interval)
FIGURE 3. Forest plot showing meta-analysis results for postpartum haemorrhage. 1040-872X ß 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins
www.co-obgyn.com
465
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Women’s health
Relative risk meta-analysis plot (random effects) Kor-Anantakul et al. (2008) [14]
3.55(1.48, 8.55)
Larsson et al. (2011) [15*]
0.71 (0.27, 1.86)
Geller et al. (2010) [17*]
0.87 (0.29, 2.55)
Holm et al. (2012) [18*]
1.28 (1.19, 1.38)
Liu et al. (2007) [19]
0.24 (0.14, 0.44)
Combined [random]
091 (0.39, 2.13) 0.1
0.2
0.5
1
2
5
10
Relative risk (95% confidence interval)
FIGURE 4. Forest plot showing meta-analysis for blood transfusion.
meta-analysis interpretation is made difficult by the observational nature of the data synthesized, this first attempt at filling a gap in the existing literature merits consideration. Existing evidence syntheses, including the current National Institute of Health and Clinical Excellence guidelines [23], do not analyse outcomes in relation to antenatal planned mode of delivery, thus deeming study methodology and results inaccurate and misrepresentative. Our findings challenge existing dogma about benefits of vaginal birth and provide a clear demonstration of what evidence women need to be made aware of during antenatal counselling. The surgical nature of a caesarean section may augment the association between planned caesarean section and an increased risk of maternal complications, such as risk of wound infection and rehospitalization [24,25]; however, existing comorbidities, such as preeclampsia and maternal age, often compound maternal morbidity, and the association between a planned mode of delivery and an increased risk of morbidity has not been established [26,27]. Comparison based on intended mode of delivery has been difficult, in order to clarify an association between PPH and planned mode of delivery, particularly, as it is likely that blood loss after caesarean section is often underestimated [19,28], and therefore there is some suggestion that caesarean section is associated with a higher risk of PPH [29,30]. The blood transfusion rate is higher amongst the women who underwent caesarean section [24,31]. Susceptibility to PND may be linked to prenatal tocophobia, a preexisting maternal psychopathology, which is a significant risk factor for developing 466
www.co-obgyn.com
postpartum symptoms [32,33]. Little evidence supports the association between planned mode of delivery, notably caesarean section and PND [34,35]; however, it is probable that the inconsistencies across findings are attributed to the lack of integration of preexisting maternal mental status [36–38]. Pelvic floor morbidity is regularly associated with vaginal birth, and it is suggested that pregnancy itself is a risk factor [39,40]. However, this association may be complicated by the lack of distinction between assisted and unassisted delivery [41]. The assumption that caesarean section is protective of urinary incontinence symptoms [42–44] has been contested and current clinical practice is in consensus that there is no robust evidence [45,46]. In fact, findings have suggested that antenatal symptoms and high BMI are the major contributing factors to developing symptoms postpartum [47].
CONCLUSION The main findings of our review are relevant to obstetricians, allied health professionals and expecting mothers. Existing evidence syntheses are misrepresentative as they have been based on relatively low-quality studies and misrepresent antenatal planned mode of delivery; therefore, the current available evidence is limited in clinical applicability to base clinical practice. There is yet to be a study design that satisfies the issue at hand and applies an accommodating methodology. Considering the various factors that may impact the availability of complete data, it would be sensible to apply a decision analysis model in order to appropriately address these benefits and risks associated with Volume 26 Number 6 December 2014
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Planned caesarean section or vaginal delivery? Azam et al.
antenatal planned delivery choice. Coupled with an accurate representation of how many women undergo successful planned modes of delivery and the ratio of maternal outcomes within each group, it may be possible to forecast the likelihood of a maternal complication in association with each planned mode of delivery. Acknowledgements S.A. performed literature searches, performed data extraction and analysis, created figures and drafted the manuscript. A.K. performed data extraction and created figures. S.A.T. revised manuscript. K.S.K. conceived the review and revised figures and manuscript. Conflicts of interest The authors declare no conflicts of interest.
REFERENCES AND RECOMMENDED READING Papers of particular interest, published within the annual period of review, have been highlighted as: & of special interest && of outstanding interest 1. Belizan JM, Althabe F, Barros FC, Alexander S. Rates and implications of caesarean sections in Latin America: ecological study. BMJ 1999; 319:1397– 1400. 2. Belizan JM, Althabe F, Cafferata ML. Health consequences of the increasing caesarean section rates. Epidemiology 2007; 18:485–486. 3. Mazzoni A, Althabe F, Liu NH, et al. Women’s preference for caesarean section: a systematic review and meta-analysis of observational studies. BJOG 2011; 118:391–399. 4. Miesnik SR, Reale BJ. A review of issues surrounding medically elective cesarean delivery. J Obstet Gynecol Neonatal Nurs 2007; 36:605–615. 5. Habiba M, Kaminski M, Da Fre M, et al. Caesarean section on request: a comparison of obstetricians’ attitudes in eight European countries. BJOG 2006; 113:647–656. 6. Cotzias CS, Paterson-Brown S, Fisk NM. Obstetricians say yes to maternal request for elective caesarean section: a survey of current opinion. Eur J Obstet Gynecol Reprod Biol 2001; 97:15–16. 7. Gonen R, Tamir A, Degani S. Obstetricians’ opinions regarding patient choice in cesarean delivery. Obstet Gynecol 2002; 99:577–580. 8. Lee-Parritz A. Surgical techniques for cesarean delivery: what are the best practices? Clin Obstet Gynecol 2004; 47:286–298. 9. Nielsen TF, Hokegard KH. Cesarean section and intraoperative surgical complications. Acta Obstet Gynecol Scand 1984; 63:103–108. 10. Lavender T, Hofmeyr GJ, Neilson JP, et al. Caesarean section for non-medical reasons at term. Cochrane Database Syst Rev 2012; 3:CD004660. 11. Liberati A, Tetzlaff J, Mulrow C, et al. The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate healthcare interventions: explanation and elaboration. PLoS Med 2009; 6:e1000100. 12. Wells GA, Shea B, O’Connell D, et al. The Newcastle–Ottawa Scale (NOS) for assessing the quality of nonrandomised studies in meta-analyses. Ontario, Canada: University of Ottawa; 2013. http://www.evidencebasedpublichealth. de/download/Newcastle_Ottowa_Scale_Pope_Bruce.pdf. [Accessed 2013] 13. Higgins JPT, Altman DG, Sterne JAC, editors. Assessing risk of bias in included studies. In: Higgins JPT, Green S, editors. Cochrane handbook for systematic reviews of interventions. Version 5.1.0 [updated March 2011]. The Cochrane Collaboration; 2011. Available from www.cochrane-handbook.org. 14. Kor-Anantakul O, Suwanrath C, Lim A, Chongsuviwatwong V. Comparing complications in intended vaginal and caesarean deliveries. J Obstet Gynaecol 2008; 28:64–68. 15. Larsson C, Saltvedt S, Wiklund I, Andolf E. Planned vaginal delivery versus & planned caesarean section: short-term medical outcome analyzed according to intended mode of delivery. J Obstet Gynaecol Can 2011; 33:796–802. The authors collected data as a prospective study from 541 primiparous women and aimed to look at maternal outcomes from planned vaginal deliveries or planned caesarean sections. The intended mode of delivery was also documented and the data have shown that there were no differences in the short-term outcomes between different groups. Comparing data to previous recorded data shows an increase in the number of complications seen in planned vaginal deliveries.
16. Wesnes SL, Hunskaar S, Bo K, Rortveit G. The effect of urinary incontinence status during pregnancy and delivery mode on incontinence postpartum. A cohort study. BJOG 2009; 116:700–707. 17. Geller EJ, Wu JM, Jannelli ML, et al. Maternal outcomes associated with & planned vaginal versus planned primary cesarean delivery. Am J Perinatol 2010; 27:675–684. The authors compared the causes of maternal morbidity amongst 26 356 women between 1995 and 2005. The women were categorized based on planned vaginal delivery and planned caesarean deliveries. One of the causes they focused on was PPH. The data show that women who had planned caesarean deliveries were at a reduced risk of maternal morbidities, such as PPH, opposed to women who had planned vaginal deliveries. 18. Holm C, Langhoff-Roos J, Petersen KB, et al. Severe postpartum haemorrhage & and mode of delivery: a retrospective cohort study. BJOG 2012; 119:596– 604. The authors conducted a restrospective study looking at 382 266 women in Denmark over the period of 2001–2008. The main objective of this study was to monitor the use of blood transfusions within the first week of delivery and whether this was influenced by the mode of delivery. The mode of delivery was recorded as actual and planned to allow us to compare data amongst the groups. The authors here divided the individuals into further categories, which helps us look at the impact of labour type in correlation to mode of delivery, and whether prelabour, spontaneous labour or induction of labour determined the severity of PPH and, hence, use of blood transfusions. The data in the article strongly suggest that the use of less blood transfusions was accounted for women who had undergone planned caesarean sections opposed to other modes of delivery. 19. Liu S, Liston RM, Joseph KS, et al. Maternal Health Study Group of the Canadian Perinatal Surveillance System. Maternal mortality and severe morbidity associated with low-risk planned cesarean delivery versus planned vaginal delivery at term. CMAJ 2007; 176:455–460. 20. Hannah ME, Hannah WJ, Hewson SA, et al. Planned caesarean section versus planned vaginal birth for breech presentation at term: a randomised multicentre trial. Term Breech Trial Collaborative Group. Lancet 2000; 356:1375–1383. 21. Hannah ME, Hannah WJ, Hodnett ED, et al. World Health Organization 2005 Global Survey on Maternal and Perinatal Health Research Group. Outcomes at 3 months after planned cesarean vs planned vaginal delivery for breech presentation at term: the international randomized Term Breech Trial. JAMA 2002; 287:1822–1831. 22. Hannah ME, Whyte H, Hannah WJ, et al. Maternal outcomes at 2 years after planned cesarean section versus planned vaginal birth for breech presentation at term: the international randomized term breech trial. Am J Obstet Gynecol 2004; 191:917–927. 23. NICE. Caesarean section. Clinical guideline 132 National Institute for Health and Clinical Excellence 2011 (in press). 24. Villar J, Carroli G, Zavaleta N, et al. World Health Organization 2005 Global Survey on Maternal and Perinatal Health Research Group. Maternal and neonatal individual risks and benefits associated with caesarean delivery: multicentre prospective study. BMJ 2007; 335:1025–1029. 25. Declercq E, Barger M, Cabral HJ, et al. Maternal outcomes associated with planned primary cesarean births compared with planned vaginal births. Obstet Gynecol 2007; 109:669–677. 26. Wax JR. Maternal request cesarean versus planned spontaneous vaginal delivery: maternal morbidity and short term outcomes. Semin Perinatol 2006; 30:247–252. 27. Gilliam M. Cesarean delivery on request: reproductive consequences. Semin Perinatol 2006; 30:257–260. 28. Allen VM, O’Connell CM, Liston RM, Baskett TF. Maternal morbidity associated with cesarean delivery without labor compared with spontaneous onset of labor at term. Obstet Gynecol 2003; 102:477–482. 29. Rossen J, Okland I, Nilsen OB, Eggebo TM. Is there an increase of postpartum hemorrhage, and is severe hemorrhage associated with more frequent use of obstetric interventions? Acta Obstet Gynecol Scand 2010; 89:1248– 1255. 30. Waterstone M, Bewley S, Wolfe C. Incidence and predictors of severe obstetric morbidity: case-control study. BMJ 2001; 322:1089–1093. 31. Burrows LJ, Meyn LA, Weber AM. Maternal morbidity associated with vaginal versus cesarean delivery. Obstet Gynecol 2004; 103:907–912. 32. Nielsen Forman D, Videbech P, Hedegaard M, et al. Postpartum depression: identification of women at risk. BJOG 2000; 107:1210–1217. 33. Soderquist J, Wijma B, Thorbert G, Wijma K. Risk factors in pregnancy for posttraumatic stress and depression after childbirth. BJOG 2009; 116:672– 680. 34. Carter FA, Frampton CM, Mulder RT. Cesarean section and postpartum depression: a review of the evidence examining the link. Psychosom Med 2006; 68:321–330. 35. Patel RR, Murphy DJ, Peters TJ. Operative delivery and postnatal depression: a cohort study. BMJ 2005; 330:879. 36. Fisher J, Astbury J, Smith A. Adverse psychological impact of operative obstetric interventions: a prospective longitudinal study. Aust N Z J Psychiatry 1997; 31:728–738. 37. Ryding EL, Wijma K, Wijma B. Psychological impact of emergency cesarean section in comparison with elective cesarean section, instrumental and normal vaginal delivery. J Psychosom Obstet Gynaecol 1998; 19:135–144.
1040-872X ß 2014 Wolters Kluwer Health | Lippincott Williams & Wilkins
www.co-obgyn.com
467
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.
Women’s health 38. Lydon-Rochelle MT, Holt VL, Martin DP. Delivery method and self-reported postpartum general health status among primiparous women. Paediatr Perinat Epidemiol 2001; 15:232–240. 39. McKinnie V, Swift SE, Wang W, et al. The effect of pregnancy and mode of delivery on the prevalence of urinary and fecal incontinence. Am J Obstet Gynecol 2005; 193:512–517. 40. Ekstrom A, Altman D, Wiklund I, et al. Planned cesarean section versus planned vaginal delivery: comparison of lower urinary tract symptoms. Int Urogynecol J Pelvic Floor Dysfunct 2008; 19:459–465. 41. Pretlove SJ, Thompson PJ, Toozs-Hobson PM, et al. Does the mode of delivery predispose women to anal incontinence in the first year postpartum? A comparative systematic review. BJOG 2008; 115:421–434. 42. Farrell SA, Allen VM, Baskett TF. Parturition and urinary incontinence in primiparas. Obstet Gynecol 2001; 97:350–356.
468
www.co-obgyn.com
43. Van Brummen HJ, Bruinse HW, van de Pol G, et al. The effect of vaginal and cesarean delivery on lower urinary tract symptoms: What makes the difference? Int Urogynecol J Pelvic Floor Dysfunct 2007; 18:133–139. 44. Abramov Y, Sand PK, Botros SM, et al. Risk factors for female anal incontinence: new insight through the Evanston-Northwestern twin sisters study. Obstet Gynecol 2005; 106:726–732. 45. MacArthur C, Glazener C, Lancashire R, et al. Exclusive caesarean section delivery and subsequent urinary and faecal incontinence: a 12-year longitudinal study. BJOG 2011; 118:1001–1007. 46. Nama V, Wilcock F. Caesarean section on maternal request: is justification necessary? Obstet Gynaecol 2011; 13:263–269. 47. Burgio KL, Borello-France D, Richter HE, et al. Pelvic Floor Disorders Network. Risk factors for fecal and urinary incontinence after childbirth: the childbirth and pelvic symptoms study. American J Gastroenterol 2007; 102:1998–2004.
Volume 26 Number 6 December 2014
Copyright © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.