MIRANDA G. LOUTET
Every year 300,000 women die during childbirth, and 99% of these deaths occur in low- and middle-income countries (LMICs) . Access to Caesarean sections (C-sections) is a requirement for safe childbirth, and when medically indicated, provide a life-saving intervention. Globally, there is both an overly high frequency of C-sections used in some countries, and concurrently, low use in other countries. The underuse of C-sections is most commonly due to a lack of access to surgical and secondary healthcare services and facilities. Therefore, a Lancet Commission on global surgery recommended that countries prioritize investment in obstetric surgery in order to implement the World Health Assembly’s resolution to include emergency and essential surgery as a component of universal health coverage (UHC) and meet Sustainable Development Goal 3.8 . However, both under and over usage of C-sections can contribute to adverse health outcomes because, as is true with many surgeries, there is a chance of more blood loss, infections, longer recovery, and a higher risk of death . This is especially apparent in low-resource settings where there may be an absence of adequate facilities, skilled birth attendants and comprehensive healthcare to conduct C-sections safely. There is also a lack of consensus in the literature on the target rate of C-section use within countries, but the World Health Organization (WHO) has recommended that at a population level, the beneficial effect of C-sections on mortality is only observed for rates up to 10-15% and beyond this may incur no benefit or may even be harmful . A recent Lancet series revealed that C-section use is increasing at an unprecedented and unjustified rate, and highlighted the harms that may come with over-use of C-sections and ways to mitigate these harms [3, 5, 6].
Changing global trends
Since 2000, the global C-section rate has almost doubled, from 16 million C-sections (12.1% of births) to 29.7 million C-sections (21.1% of births) in 2015 . Although there is a lot of variation between regions, from 5% of births in southern Africa to 60% in Latin America, all regions of the world have experienced an increase in C-section rates over the last decade.
Among countries highlighted in the Lancet report, two-thirds had a C-section rate of over the recommended 15%, and in some parts of southeast Europe, Latin America, and China, C-sections outnumber vaginal deliveries . The latest data from the Lancet series showed that rates of C-section use are very high in LMICs, which may reflect both increases in the number of women giving birth in medical institutions, and more C-sections being performed in those medical institutions. However, there is a lot of variation between countries in relation to these changes in medical institution trends. For example, in countries where more than 95% of births occur in health facilities, the C-section rates are as low as 6% (in Turkmenistan) to as high as 56% (in Brazil) . In comparison, the majority of countries where less than 60% of births occur in a health facility have very low C-section rates .
The Lancet report also shows that there are large disparities within countries due to low rates of C-section use among rural and vulnerable populations . In LMICs, the frequency of C-sections is five times higher in the richest segments of the population compared to the poorest. C-sections are more frequent in private rather than public health care facilities, which often aligns with healthcare access for the richest and poorest segments of the population respectively. In Brazil, 80-90% of births are by C-section in private facilities, compared to 30-40% of births in public facilities . Within a country, differences are also stark between rural and urban populations, for example, the national C-section rate in Ethiopia is 2%, but in the capital city of Addis Ababa, it is 21% 
The World Congress of Gynaecology and Obstetrics (FIGO) position paper the accompanied the Lancet series, very poignantly pointed out that these highly variable rates both between and within countries demonstrate that neither an increase in complex pregnancies nor evidence-based medicine offer reasons for the sharp increase in C-section use .
The harms of C-section over-use
Although numbers of C-sections have been going up globally over the last decade, the risks have not been reduced . Risks often depend on where in the world the operation is taking place because the risk of maternal mortality and morbidity associated with C-sections is lowest in high-resource settings and high in low-resource settings . Data from the WHO in 2013 showed that 62% of women from LMICs had a severe acute maternal morbidity (SAMM) (See Endnotes ) after a C-section compared to 37% from vaginal birth [10, 11]. This is in contrast to less than 1% of women in high-income countries experience a SAMM as a result of a C-section or vaginal birth. However, even in high-income countries the risk of SAMM is consistently greater following a C-section compared to a vaginal birth [12, 13]. A recent systematic review and meta-analysis on maternal and perinatal mortality following C-section in LMICs reported that the risk of maternal death in women who had C-sections was 7.6 per 1000 C-section procedures in LMICs, which is 100 times higher than in high-income countries where the rate is approximately 8 maternal deaths per 100,000 C-section procedures . The authors hypothesized that complications that occur during or following C-sections are particularly severe in LMICs because of the lack of resources and trained personnel needed for managing complications.
There is emerging evidence that may have less of a health human resource-difference effect because babies born by C-section may have different bacterial, hormonal and physical exposures due to the mode of delivery, which may alter their physiology . Recent data suggests that being born by C-section may alter a newborn’s immune system and gut microbiome development (See Endnotes ), which may lead to an increased likelihood of adverse health outcomes such as infections, allergy and asthma .
Tackling C-section over-use
The WHO estimates that 6.2 million unnecessary (not medically indicated) C-sections are being performed each year . In response to the doubling in C-section rates, in particular elective C-sections, the Lancet published a special series on “Optimizing caesarean section use” and the scientists at the World Congress of Gynaecology and Obstetrics conference in 2018 put out a call for more research to specifically address the non-medical reasons that are driving this increase and interventions that are specifically designed to reduce unnecessary C-sections .
The Lancet series identified a number of reasons and potential areas to intervene . Firstly, the researchers pointed out that there is a need to address women’s fears, concerns and misperceptions about labour. This is compounded by conflicting guidance from national and international regulatory bodies such that the WHO recommends that C-sections should not be used if not clinically indicated, but the United Kingdom’s NICE guidelines suggest that a woman should be offered a planned C-section if she wishes to consider this option . This could be easily mitigated through clear and consistent messaging from healthcare providers and national policies, such as the recent WHO guidance on “Non-clinical interventions to reduce unnecessary caesarean sections,” which recommends that more care be provided by midwives in order to provide a more individualized approach to labour and delivery . The midwifery-obstetrician model has been associated with more vaginal births, safer outcomes, positive maternal experiences and lower costs .
Secondly, the latest data in the Lancet series suggests that women identify health providers as the most important influence on their decision about mode of delivery; however, this creates a power imbalance because recent data also show that physicians may be influenced by health facility pressures including legal, scheduling and financial incentives . The Lancet article provides evidence that physicians are more likely to be sued for complications during vaginal delivery compared to unnecessary C-section delivery ; that in some settings, C-sections occur most often during working hours and on Fridays to increase convenience ; and that doctors are paid more for performing a C-section than a vaginal birth . Therefore, the FIGO position paper strongly recommends the need for interventions at a health system level, including financial strategies that remunerate vaginal deliveries and C-sections equally .
In conclusion, there is no debate that underuse of C-sections (when medically indicated) leads to maternal and perinatal mortality and morbidity and there is a great need to ensure universal access to safe C-sections for those who need it. However, in many countries and cities within countries the pendulum has swung the other way, such that the number of unnecessary C-sections is increasing, which may have both short- and long-term effects on mothers and children. The authors of the Lancet series and FIGO position paper advocate for the need for more research on interventions to reduce the number of unnecessary C-sections; however, they poignantly acknowledge that the first step for success is country-level recognition of the problem.
 Defined as “a very ill pregnant or recently delivered woman who would have died had it not been that luck and good care was on her side” .
 The gut microbiome contains all microorganisms that exist within the gut including bacteria, viruses, fungi, protists and archaea .
 WHO, UNICEF, UNFPA, World Bank Group and the United Nations Population Division. (2015). Trends in maternal mortality: 1990 to 2015. Estimates by WHO, UNICEF. UNFPA, World Bank group and the United Nations Population Division. Retrieved from https://www.who.int/reproductivehealth/publications/monitoring/maternal-mortality-2015/en/
 Price, R., Makasa, E., and Hollands, M. (2015). World Health Assembly Resolution WHA68.15: “Strengthening Emergency and Essential Surgical Care and Anesthesia as a Component of Universal Health Coverage”—Addressing the Public Health Gaps Arising From Lack of Safe, Affordable and Accessible Surgical and Anesthetic Services. World Journal of Surgery, 39(9):2115-25. DOI: 10.1007/s00268-015-3153-y
 Sandall, J., Tribe, R.M., Avery, L., Mola, G., Visser, G.H.A., Homer, C.S.E., et al. (2018). Short-term and Long-term Effects of Caesarean Section on the Health of Women and Children. The Lancet, 392(10155):1349-57. DOI: 10.1016/S0140-6736(18)31930-5
 Betrán, A.P., Torloni, M.R., Zhang, J.J., Gülmezoglu, A.M., and WHO Working Group on Caesarean Section. (2016) WHO Statement on Caesarean Section Rates. BJOG: An International Journal of Obstetrics & Gynaecology, 123(5):667-70. DOI: 10.1111/1471-0528.13526
 Boerma, T., Ronsmans, C., Melesse, D.Y., Barros, A.J.D., Barros, F.C., Juan, L., et al. (2018). Global Epidemiology of Use of and Disparities in Caesarean Cections. The Lancet, 392(10155):1341-8. DOI: 10.1016/S0140-6736(18)31928-7
 Betrán, A.P., Temmerman, M., Kingdon, C., Mohiddin, A., Opiyo, N., Torloni, M.R., et al. (2018). Interventions to Reduce Unnecessary Caesarean Sections in Healthy Women and Babies. The Lancet, 392(10155):1358-68. DOI: 10.1016/S0140-6736(18)31927-5
 Visser, G.H.A., Ayres-de-Campos, D., Barnea, E.R., de Bernis, L., Di Renzo, G.C., Vidarte, M.F.E., et al. (2018). FIGO Position Paper: How to Stop the Caesarean Section Epidemic. The Lancet, 392(10155):1286-7. DOI: 10.1016/S0140-6736(18)32113-5
 Sobhy, S., Arroyo-Manzano, D., Murugesu, N., Karthikeyan, G., Kumar, V., Kaur, I., et al. (2019). Maternal and Perinatal Mortality and Complications Associated with Caesarean Section in Low-Income and Middle-Income Countries: A Systematic Review and Meta-Analysis. The Lancet, 393(10184):1973-82. DOI: 10.1016/S0140-6736(18)32386-9
 Say, L., Pattinson, R.C., Gülmezoglu, A.M. (2004). WHO Systematic Review of Maternal Morbidity and Mortality: The Prevalence of Severe Acute Maternal Morbidity (Near Miss). Reproductive Health, 1(1):3. DOI: 10.1186/1742-4755-1-3
 Souza, J.P., Gülmezoglu, A.M., Vogel, J., Carroli, G., Lumbiganon, P., Qureshi, Z., et al. (2013). Moving Beyond Essential Interventions for Reduction of Maternal Mortality (The WHO Multicountry Survey on Maternal and Newborn Health): A Cross-Sectional Study. The Lancet, 381(9879):1747-55. DOI: 10.1016/S0140-6736(13)60686-8
 Gebhardt, G.S., Fawcus, S., Moodley, J., Farina, Z., and National Committee for Confidential Enquiries into Maternal Deaths in South Africa. (2015). Maternal Death and Caesarean Section in South Africa: Results from the 2011-2013 Saving Mothers Report of the National Committee for Confidential Enquiries into Maternal Deaths. South African Medical Journal, 105(4):287-91. DOI: 10.7196/samj.9351
 Liu, S., Liston, R.M., Joseph, K.S., Heaman, M., Sauve, R., Kramer, M.S., and Maternal Health Study Group of the Canadian Perinatal Surveillance System. (2007). Maternal Mortality and Severe Morbidity Associated With Low-Risk Planned Cesarean Delivery Versus Planned Vaginal Delivery at Term. CMAJ, 176(4):455-60. DOI: 10.1503/cmaj.060870
 Pallasmaa, N., Ekblad, U., and Gissler, M. (2008). Severe Maternal Morbidity and the Mode of Delivery. Acta Obstetricia et Gynecologica Scandinavica, 87(6):662-8. DOI: 10.1080/00016340802108763
 Ursell, L.K., Metcalf, J.L., Parfrey, L.W., and Knight, R. (2012). Defining the Human Microbiome. Nutrition Reviews, 70(Suppl 1):S38-S44. DOI: 10.1111/j.1753-4887.2012.00493.x
 Tita, A.T.N., Landon, M.B., Spong, C.Y., Lai, Y., Leveno, K.J., Varner, M.W., et al. (2009). Timing of Elective Repeat Cesarean Delivery at Term and Neonatal Outcomes. New England Journal of Medicine, 360(2):111-20. DOI: 10.1056/NEJMoa0803267
 Gibbons, L., Belizán, J.M., Lauer, J.A., Betrán, A.P., Merialdi, M., and Althabe, F. (2010). The Global Numbers and Costs of Additionally Needed and Unnecessary Caesarean Sections Performed per Year: Overuse as a Barrier to Universal Coverage. World Health Report, 30:1-31.
 The Lancet. (2018). Stemming the Global Caesarean Section Epidemic. The Lancet, 392(10155):1279. DOI: 10.1016/S0140-6736(18)32394-8
 World Health Organization. (2018). WHO recommendations non-clinical interventions to reduce unnecessary caesarean sections. Retrieved from https://www.who.int/reproductivehealth/publications/non-clinical-interventions-to-reduce-cs/en/.
 Studdert, D.M., Mello, M.M., Gawande, A.A., Gandhi, T.K., Kachalia, A., Yoon, C., et al. (2006). Claims, Errors, and Compensation Payments in Medical Malpractice Litigation. New England Journal of Medicine, 354(19):2024-33. DOI: 10.1056/NEJMsa054479
 Dweik, D., Girasek, E., Mészáros, G., Töreki, A., Keresztúri, A., and Pál, A. (2014). Non‐medical Determinants of Cesarean Section in a Medically Dominated Maternity System. Acta Obstetricia et Gynecologica Scandinavica, 93(10):1025-33. DOI: 10.1111/aogs.12466
 Murray, S.F. (2000). Relation between private health insurance and high rates of caesarean section in Chile: qualitative and quantitative study. BMJ, 321(7275):1501-5. DOI: 10.1136/bmj.321.7275.1501