section name header

Evidence summaries

Method of Delivery and Pregnancy Outcomes

Caesarean delivery appears to increase the risk of severe maternal and neonatal morbidity and mortality in cephalic presentations. Level of evidence: "B"

In the WHO global survey the aim was to assess the risks and benefits associated with caesarean delivery compared with vaginal delivery. In Asia,1 data for 109 101 of 112 152 deliveries (97% coverage) was obtained, and 107 950 deliveries analysed. The overall rate of caesarean section (CS) was 27.3% (n=29 428) and of operative vaginal delivery was 3.2% (n=3465). Practices in the 9 Asian countries differed substantially: rates in 4 countries exceeded 30% (China 46.2%), whereas rates in 5 countries were less than 21%. Risk of maternal mortality and morbidity (maternal mortality, admission to intensive care unit [ICU], blood transfusion, hysterectomy, or internal iliac artery ligation) was increased for operative vaginal delivery (adjusted odds ratio 2.1, 95% CI 1.7 to 2.6) and all types of CS (antepartum without indication OR 2.7, 1.4 to 5.5; antepartum with indication OR 10.6, 9.3 to12.0; intrapartum without indication OR 14.2, 9.8 to 20.7; intrapartum with indication OR 14.5, 13.2 to16.0). For breech presentation, caesarean section, either antepartum (0.2, 0.1 to 0.3) or intrapartum (0.3, 0.2 to 0.4), was associated with improved perinatal outcomes, but also with increased risk of stay in neonatal ICU (2.0, 1.1 to 3.6; and 2.1, 1.2 to 3.7, respectively).

In the prospective cohort study in 8 Latin American countries 2 data were available for 97095/106 546 deliveries (91% coverage). The overall rate of caesarean section was 33%. The risk of severe maternal morbidity was increased in caesarean delivery compared with vaginal delivery (OR 2.0, 95% CI 1.6 to 2.5 for intrapartum caesarean, and OR 2.3, 95% CI 1.7 to 3.1 for elective caesarean). The risk of antibiotic treatment for women having caesarean was 5 times that of women having vaginal deliveries. With cephalic presentation, there was a nonsignificant trend towards a reduced odds ratio for fetal death with elective caesarean. However, intrapartum and elective caesarean increased the risk for a stay of seven or more days in neonatal intensive care (OR 2.1 95% CI 1.8 to 2.6 and OR 1.9, 95% CI 1.6 to 2.3, respectively) and the risk of neonatal mortality up to hospital discharge (OR 1.7, 95% CI 1.3 to 2.2 and OR 1.9, 95% CI 1.5 to 2.6, respectively), which remained higher even after exclusion of all caesarean deliveries for fetal distress. With breech presentation, caesarean delivery had a large protective effect for fetal death.

A meta-analysis 3 included 7 174 787 live recorded births in Denmark, Scotland, England, and Australia. Of these, 23% (range by jurisdiction 17% to 29%) were by CS, of which 727 755 (43%, range 38% to 57%) were elective. Compared to vaginally born children, risk of infection was greater among CS-born children (hazard ratio (HR) from random effects model, HR 1.10, 95% CI 1.09 to 1.12, p < 0.001). The risk was higher following both elective (HR 1.13, 95% CI 1.12 to 1.13, p < 0.001) and emergency CS (HR 1.09, 95% CI 1.06 to 1.12, p < 0.001). Increased risks persisted to 5 years and were highest for respiratory, gastrointestinal, and viral infections.

para>Comment: The quality of evidence is upgraded by consistent findings and big sample size (strong evidence of association).

    References

    • Lumbiganon P, Laopaiboon M, Gülmezoglu AM, et al, for the World Health Organization Global Survey on Maternal and Perinatal Health Research Group. Method of delivery and pregnancy outcomes in Asia: the WHO global survey on maternal and perinatal health 2007-08. Lancet 2010 ;375(9713):490-499. [PubMed]
    • 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(7628):1025. [PubMed]
    • Miller JE, Goldacre R, Moore HC et al. Mode of birth and risk of infection-related hospitalisation in childhood: A population cohort study of 7.17 million births from 4 high-income countries. PLoS Med 2020;17(11):e1003429. [PubMed]

Primary/Secondary Keywords