Evidence - Cesarean section

Cesarean delivery (C-section) is the most frequently performed surgery in women worldwide, and its frequency is continuously increasing. While it was previously associated with high risks for both mother and child, it is now considered a safe procedure. Nevertheless, there is limited knowledge about potential short- and long-term health effects for both mother and child. This leads to uncertainties in decision-making regarding the optimal birth method.

A primary C-section is performed before labor has begun, meaning there have been no contractions affecting the cervix nor a (premature) rupture of membranes.

In contrast, a secondary C-section occurs when labor has already started, either through cervical contractions or a premature rupture of membranes.

• C-section rate 2014 in Germany: 31.8% (Federal Statistical Office)
• Development since 1991: Doubling of the rate (1991: 15.3%)
• Stabilization: Constant rate for three years
• Decline since 2014: Introduction of the risk-adjusted C-section rate led to a slight decrease

References: 

1. Macfarlane A, Blondel B, Mohangoo A, Cuttini M, Nijhuis J, Novak Z, et al. Wide differences in mode of delivery within Europe: risk-stratified analyses of aggregated routine data from the Euro-Peristat study. BJOG An Int J Obstet Gynaecol [Internet]. 2016 Mar;123(4):559–68. Available from: http://www.ncbi.nlm.nih.gov/pubmed/25753683 
2. World Health Organization Human Reproduction Programme, 10 April 2015. WHO Statement on caesarean section rates. Reprod Health Matters [Internet]. 2015 Jan 27;23(45):149–50. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26278843
3. Federal Statistical Office. Federal Statistical Office [Internet]. 2015. Available from: https://www.destatis.de/DE/Presse/Pressemitteilungen/_inhalt.html 
4. IQTIG - Institute for Quality Assurance and Transparency in Healthcare. National evaluation for the reporting year 2015 Obstetrics Quality Indicators [Internet]. 2016. Available from: http://www.iqtig.org 

• Early education: Pregnant women should receive evidence-based information to make an informed decision about the birth method.
• Consideration of perspectives: The perspectives and concerns of women should be included in the consultation process.
• Individual support: Women who desire a cesarean section should receive comprehensive counseling during pregnancy.
• Clear communication: Information should be provided in language accessible to laypersons.
• Consideration of special needs: Information should be tailored for:
  • Women from ethnic minorities (language, culture, religion)
  • Women whose native language is not German
  • Illiterate women or women with disabilities/learning difficulties
• Contents of education:
  • Indications for a cesarean section
  • Procedure of the operation
  • Risks and benefits
  • Impact on future pregnancies
• Emotional stress: Every cesarean birth is experienced as physically and emotionally challenging.
• Psychological stress: Women with an elective or non-urgent cesarean may experience similar psychological difficulties as with an emergency cesarean.
• Importance of information: More knowledge about the cesarean process can help positively influence the experience.

• Absolute indication: Cesarean section is absolutely necessary to save the mother and/or child.
• Examples of absolute indications:
  • Transverse position of the child
  • (Impending) uterine rupture
  • Placenta previa
  • Premature placental abruption
• Frequency: Absolute indications account for less than 10% of all cesarean sections.
• Relative indication: In about 90% of cases, a weighing of risks for mother and child occurs.
• Early education: The risk-benefit assessment between vaginal birth and cesarean section should occur in a timely manner.
• Goal: Participatory decision-making through comprehensive information.

Summary of study results on vaginal birth vs. cesarean section

Maternal outcomes

• Hysterectomies after postpartum hemorrhage: Less common with vaginal birth (RR 2.31, CI 1.30 – 4.09; n=2,339,186, 8.2%).
• Assisted ventilation or intubation: Less common (RR 2.21, CI 0.99 – 4.90; n=2,339,186, 8.2%).
• Cardiac arrest: Less common after vaginal birth (RR 4.91, CI 3.95 – 6.11; n=2,339,186, 8.2%).
• Severe acute maternal morbidity (SAMM): Lower rate, but no difference for women with BMI ≥ 50 (OR 3.9, CI 3.5 – 4.3; n=355,841, 8.6%).
• Deep vein thrombosis: Less common after vaginal birth (RR 2.20, CI 1.51 – 3.20; n=2,339,186, 8.2%).
• Maternal mortality: Less common after vaginal birth (OR 4.0, CI 1.9 - 8.2; n=355,841, 8.6%).
• Postpartum infections: Less common after vaginal birth (RR 2.85, CI 2.52 – 3.21; n=2,339,186, 8.2%).
• Anesthesia complications: Less frequent after vaginal birth (RR 2.5, CI 2.22 – 2.86; n=2,339,186, 8.2%).
• Length of hospital stay: Shorter with vaginal birth (Difference: 1.47 days, CI 1.46 – 1.49).
• Obstetric shock: More common with vaginal birth (RR 0.33, CI 0.11 – 0.99; n=2,339,186, 8.2%).
• Early postpartum hemorrhage: Tends to be more common after vaginal birth (OR 0.23, CI 0.06 – 0.94; n=4,048, 35%).
• Pain (perineum and abdomen): More intense during and three days after birth (VAS difference 6.3 points during birth, 0.7 points 3 days postpartum).
• Blood transfusions: More likely required after vaginal birth (RR 0.20, CI 0.20 – 0.64).
• Acute renal failure, uterine rupture, intraoperative trauma, pulmonary embolism, injuries (bladder, ureters, cervix, vagina): No significant differences between vaginal birth and cesarean section.

Neonatal outcomes

• Neonatal mortality: Less common after vaginal birth (RR 2.4, CI 2.20 – 2.65; n=8,026,405, 7.9%).
• Hypoxic-ischemic encephalopathy, intracranial hemorrhages, neurological morbidity: No difference between both birth methods.
• Neonatal respiratory morbidity: No significant difference.
• Admission to the Neonatal Intensive Care Unit (NICU): Less frequently necessary after vaginal birth (RR 2.20, CI 1.40 – 3.18).
• 5-minute Apgar score < 7: No difference.

Long-term outcomes after cesarean section

Long-term effects on women

Ectopic pregnancy

• Inconsistent results:
  • in some studies with increased risk (OR 1.21; CI 1.04 – 1.40; n=312,026).

Stillbirth & miscarriage

• Stillbirth:
  • Inconsistent results: in some studies less common, in others more common after cesarean (pooled OR 1.27; CI 1.15 – 1.40; n=703,562, 8 studies).
• Miscarriage:
  • (52) Increased risk (pooled OR 1.17; CI 1.03 – 1.32; n=151,412, 4 studies).

Infertility

• Delayed fertility after cesarean section:
  • OR 0.90 (CI 0.86 – 0.93).
  • Lower pregnancy rate (RR 0.91; CI 0.87 – 0.95).
  • Increased risk of infertility (pooled OR 1.60; CI 1.45 – 1.76; n=3,692,014, 11 studies).

Long-term effects on children

Cerebral palsy

• No general difference (OR 1.29; CI 0.92 – 1.79; n=1,696,390).
• Higher risk after emergency cesarean (OR 2.17; CI 1.58 – 2.98).
• Increased risk in term-born babies after cesarean (OR 1.6; CI 1.05 – 2.44).

Inflammatory bowel diseases

• Varying results:
  • Inconsistent results

Overweight & obesity

• Increased risk after cesarean:
  • OR 1.33 (CI 1.19 – 1.48).
  • Overweight: OR 1.26 (CI 1.16 – 1.38).
  • Obesity: OR 1.22 (CI 1.05 – 1.42).
  • Overweight in children 3-13 years: OR 1.22 (CI 1.06 – 1.41).

Childhood asthma

• Higher risk after cesarean:
  • OR 1.16 (CI 1.14 – 1.29; 26 studies).
  • OR 1.21 (CI 1.11 – 1.32; n=887,960, 13 studies).

Health issues & mortality

• Increased risk after planned cesarean:
  • Type I diabetes: HR 1.35 (CI 1.05 – 1.75; n=312,287).
  • Higher hospital admissions for asthma & mortality observed.

Further long-term effects on women

Urinary incontinence & uterine prolapse

• Lower risk after cesarean:
  • Urinary incontinence: OR 0.56 (CI 0.47 – 0.66; n=58,900, 8 studies).
  • Uterine prolapse: OR 0.29 (CI 0.17 – 0.51; n=39,208, 2 studies).

Placental complications in subsequent pregnancies

• Higher risk for:
  • Placenta previa (OR 1.74; CI 1.62 – 1.87; n=7,101,692, 10 studies).
  • Placenta accreta (OR 2.95; CI 1.32 – 6.60; n=705,108, 3 studies).
  • Premature placental abruption (OR 1.38; CI 1.27 – 1.49; n=5,667,160, 6 studies).
  • Uterine rupture (OR 25.81; CI 10.96 – 60.76; n=841,209, 4 studies).

Bleeding & hysterectomy

• Higher risk for:
  • Hysterectomy (OR 3.85; CI 1.06 – 14.02; n=167,674, 2 studies).
  • Antepartum bleeding (OR 1.22; CI 1.09 – 1.36; n=91,429, 2 studies).
• Lower risk for:
  • Postpartum bleeding (OR 0.72; CI 0.55 – 0.95; n=259,103, 2 studies).

References: 

1. NICE. Cesarean Section Clinical guideline [CG132]. 2011; Available from: https://www.nice.org.uk/guidance/cg132
2. National Institute for Health and Clinical Excellence. Caesarean section : Evidence Update March 2013. Natl Inst Heal Clin Excell. 2013;(March):1–28. 
3. NICE. 4-year surveillance (2017) - summary of new evidence Cesarean section (2011) NICE guideline CG132 [Internet]. Available from: https://www.nice.org.uk/guidance/cg132/evidence/appendix-a-summary-of-newevidence-pdf-2736386032 
4. Caesarean section Caesarean section Clinical guideline [Internet]. 2011. Available from: https://www.nice.org.uk/guidance/cg132/resources/caesarean-section-pdf35109507009733 
5. Homer C, Kurinczuk J, Spark P, Brocklehurst P, Knight M. Planned vaginal delivery or planned caesarean delivery in women with extreme obesity. BJOG An Int J Obstet Gynaecol [Internet]. 2011 Mar;118(4):480–7. Available from: http://www.ncbi.nlm.nih.gov/pubmed/21244616
6. MacDorman MF, Declercq E, Menacker F, Malloy MH. Neonatal Mortality for Primary Cesarean and Vaginal Births to Low-Risk Women: Application of an &quot;Intentionto-Treat&quot; Model. Birth [Internet]. 2008 Mar;35(1):3–8. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18307481 
7. Geller EJ, Wu JM, Jannelli ML, Nguyen T V, Visco AG. Neonatal outcomes associated with planned vaginal versus planned primary cesarean delivery. J Perinatol [Internet]. 2010 Apr 8;30(4):258–64. Available from: http://www.ncbi.nlm.nih.gov/pubmed/19812591 
8. Geller E, Wu J, Jannelli M, Nguyen T, Visco A. Maternal Outcomes Associated with Planned Vaginal Versus Planned Primary Cesarean Delivery. Am J Perinatol [Internet]. 2010 Oct 16;27(09):675–84. Available from: http://www.ncbi.nlm.nih.gov/pubmed/20235001 
9. Dahlgren LS, von Dadelszen P, Christilaw J, Janssen PA, Lisonkova S, Marquette GP, et al. Caesarean section on maternal request: risks and benefits in healthy nulliparous women and their infants. J Obstet Gynaecol Can [Internet]. 2009 Sep;31(9):808–17. Available from: https://linkinghub.elsevier.com/retrieve/pii/S1701216316342992 
10. Allen VM, O’Connell CM, Baskett TF. Maternal Morbidity Associated With Cesarean Delivery Without Labor Compared With Induction of Labor at Term. Obstet Gynecol [Internet]. 2006 Aug;108(2):286–94. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16880297 
11. Liu S, Liston RM, Joseph KS, Heaman M, Sauve R, Kramer MS, et al. Maternal mortality and severe morbidity associated with low-risk planned cesarean delivery versus planned vaginal delivery at term. Can Med Assoc J [Internet]. 2007 Feb 13;176(4):455–60. Available from: http://www.ncbi.nlm.nih.gov/pubmed/17296957 
12. Deneux-Tharaux C, Carmona E, Bouvier-Colle M-H, Bréart G. Postpartum Maternal Mortality and Cesarean Delivery. Obstet Gynecol [Internet]. 2006 Sep;108(3, Part 1):541–8. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16946213 
13. Schindl M, Birner P, Reingrabner M, Joura E, Husslein P, Langer M. Elective cesarean section vs. spontaneous delivery: a comparative study of birth experience. Acta Obstet Gynecol Scand [Internet]. 2003 Sep;82(9):834–40. Available from: http://www.ncbi.nlm.nih.gov/pubmed/12911445 
14. van Dillen J, Zwart JJ, Schutte J, Bloemenkamp KWM, van Roosmalen J. Severe acute maternal morbidity and mode of delivery in the Netherlands. Acta Obstet Gynecol Scand [Internet]. 2010 Nov;89(11):1460–5. Available from: http://doi.wiley.com/10.3109/00016349.2010.519018 
15. Keag OE, Norman JE, Stock SJ. Long-term risks and benefits associated with cesarean delivery for mother, baby, and subsequent pregnancies: Systematic review and meta-analysis. Myers JE, editor. PLOS Med [Internet]. 2018 Jan 23;15(1):e1002494. Available from: http://www.ncbi.nlm.nih.gov/pubmed/29360829 
16. Deneux-Tharaux C, Carmona E, Bouvier-Colle M-H, Bréart G. Postpartum Maternal Mortality and Cesarean Delivery. Obstet Gynecol [Internet]. 2006 Sep;108(3, Part 1):541–8. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16946213 
17. O’Neill S, Khashan A, Kenny L, Greene R, Henriksen T, Lutomski J, et al. Caesarean section and subsequent ectopic pregnancy: a systematic review and meta-analysis. BJOG An Int J Obstet Gynaecol [Internet]. 2013 May;120(6):671–80. Available from: http://www.ncbi.nlm.nih.gov/pubmed/23398899 
18. O’Neill SM, Kearney PM, Kenny LC, Khashan AS, Henriksen TB, Lutomski JE, et al. Caesarean Delivery and Subsequent Stillbirth or Miscarriage: Systematic Review and Meta-Analysis. Middleton P, editor. PLoS One [Internet]. 2013 Jan 23;8(1):e54588. Available from: http://dx.plos.org/10.1371/journal.pone.0054588 
19. O’Neill SM, Kearney PM, Kenny LC, Henriksen TB, Lutomski JE, Greene RA, et al. Caesarean delivery and subsequent pregnancy interval: a systematic review and meta-analysis. BMC Pregnancy Childbirth [Internet]. 2013 Dec 27;13(1):165. Available from: https://bmcpregnancychildbirth.biomedcentral.com/articles/10.1186/1471-239313-165
20. Gurol-Urganci I, Bou-Antoun S, Lim CP, Cromwell DA, Mahmood TA, Templeton A, et al. Impact of Caesarean section on subsequent fertility: a systematic review and metaanalysis. Hum Reprod [Internet]. 2013 Jul;28(7):1943–52. Available from: https://academic.oup.com/humrep/article-lookup/doi/10.1093/humrep/det130 
21. O’Callaghan M, MacLennan A. Cesarean Delivery and Cerebral Palsy. Obstet Gynecol [Internet]. 2013 Dec;122(6):1169–75. Available from: http://www.ncbi.nlm.nih.gov/pubmed/24201683 
22. Li Y, Tian Y, Zhu W, Gong J, Gu L, Zhang W, et al. Cesarean delivery and risk of inflammatory bowel disease: a systematic review and meta-analysis. Scand J Gastroenterol [Internet]. 2014 Jul 18;49(7):834–44. Available from: http://www.ncbi.nlm.nih.gov/pubmed/24940636 
23. Bruce A, Black M, Bhattacharya S. Mode of delivery and risk of inflammatory bowel disease in the offspring: systematic review and meta-analysis of observational studies. Inflamm Bowel Dis [Internet]. 2014 Jul;20(7):1217–26. Available from: https://academic.oup.com/ibdjournal/article/20/7/1217-1226/4579585 
24. Li H, Zhou Y, Liu J. The impact of cesarean section on offspring overweight and obesity: a systematic review and meta-analysis. Int J Obes [Internet]. 2013 Jul 4;37(7):893–9. Available from: http://www.ncbi.nlm.nih.gov/pubmed/23207407
25. Darmasseelane K, Hyde MJ, Santhakumaran S, Gale C, Modi N. Mode of Delivery and Offspring Body Mass Index, Overweight and Obesity in Adult Life: A Systematic Review and Meta-Analysis. Dewan A, editor. PLoS One [Internet]. 2014 Feb 26;9(2):e87896. Available from: https://dx.plos.org/10.1371/journal.pone.0087896
26. Huang L, Chen Q, Zhao Y, Wang W, Fang F, Bao Y. Is elective cesarean section associated with a higher risk of asthma? A meta-analysis. J Asthma [Internet]. 2015 Feb 2;52(1):16–25. Available from: http://www.tandfonline.com/doi/full/10.3109/02770903.2014.952435 
27. Black M, Bhattacharya S, Philip S, Norman JE, McLernon DJ. Planned Cesarean Delivery at Term and Adverse Outcomes in Childhood Health. JAMA [Internet]. 2015 Dec 1;314(21):2271. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26624826 

Absolute Indications

• Transverse lie of the child
• Placenta previa (partial or complete covering of the cervix)
• Premature placental abruption
• Uterine rupture (impending or occurred)
• Fetal distress (acute hypoxia, pathological CTG findings)
• HIV infection of the mother with high viral load
• Genital herpes simplex virus (HSV) infection in the 3rd trimester
• Cephalopelvic disproportion (disproportion between fetal head and maternal pelvis)
• Severe preeclampsia or eclampsia
• HELLP syndrome (severe pregnancy complication with liver dysfunction)
• Previous multiple uterine surgeries or several prior cesarean sections

Relative Indications (required after risk assessment)

• Breech presentation (especially in primiparas or under unfavorable conditions)
• Multiple pregnancies, especially with breech presentation of the leading twin
• Intrauterine growth restriction (IUGR) with abnormal Doppler sonography
• Prematurity (<36 weeks of gestation) with unfavorable factors
• Macrosomia (very large child, >4500 g with diabetes, >5000 g without diabetes)
• Fetal malformations that complicate vaginal delivery (e.g., hydrocephalus)
• Severe maternal diseases (e.g., severe cardiovascular diseases)
• Previous uterine rupture or complicated birth injury in history

Other Indications Based on Individual Decision

• Cesarean section at the request of the pregnant woman after comprehensive counseling
• HPV infection with extensive condylomas obstructing the birth canal
• Hepatitis B or C – not a general indication, except with HIV coinfection
• Condition after external version in breech presentation, if unsuccessful
• Prolonged labor with arrest of labor despite adequate labor stimulation
• Increased risk of perinatal morbidity or mortality based on individual factors

References:

DGGG. The Cesarean Section. S3-Guideline. AWMF Register No. 015/083. Ed. by the Association of the Scientific Medical Societies (AWMF). On the Internet: https://www.awmf.org/leitlinien/detail/ll/015-084.html