Pulling back the curtain on Canada’s rising C-section rate
Caesarian sections (C-sections) are among the most common surgical procedures performed on women of child-bearing age. Canada’s C-section rate has increased dramatically in the past two decades.
The national C-section rate has increased from 17% of all births in 1995 to nearly 27% in 2010. In Ontario, nearly 29% of births in 2011/12 were by C-section, with a similar rate in Alberta of 28% in 2009.
While C-sections are often the best approach to ensuring good outcomes for both mother and baby in high-risk pregnancies or complicated deliveries, rates are rising among women with low-risk pregnancies.
Sharply rising rates have led to debates about when this surgery is appropriate – and when it is not. This article highlights some of the drivers of rising C-section rates, as well as examples of where targeted approaches are attempting to reduce C-sections among low-risk pregnancies.
Ann Sprague, acting director of BORN – Ontario’s birth and pregnancy registry – says that while “everyone is interested in reducing C-section rates, you can’t tackle it all at once.” She highlights that “there are many things that drive C-section rates, including induction practices, changing demographics of child-bearing women, and general obstetric complications.” She suggests “if you look at small pieces of it you will make progress.”
Changing demographics and costs associated with C-sections
Changing demographics of Canadian women have implications for childbirth. The most significant factors are delaying child-bearing until a later age, as well as increased body mass and more pregnant women with chronic diseases. Women with one or more of these characteristics are statistically more likely to have a higher-risk pregnancy and more complications during labour, and are more likely to have a C-section.
There has also been a rise in birth weights in the past few decades. Bigger babies can mean more difficult deliveries for women.
In addition, there has been “an explosion” in the number of multiple pregnancies in Canada – driven by trends of delayed child-bearing and increased use of fertility treatments. Multiple pregnancies are more likely to be delivered by C-section, and once women have delivered by C-section, they are more likely to do so for subsequent pregnancies.
C-sections are more costly than vaginal births, because they require more resources like operating room space, anesthesiologists and nursing care, as well as a longer hospital stay. A 2006 Canadian Institute of Health Information report estimated that a C-section costs $4,600, compared with $2,800 for a vaginal birth.
Lisa Graves, Chief of Family and Community Medicine at St. Michael’s Hospital, describes C-sections as “an important tool in maternal care, that when appropriately received and timed, saves lives of women and children who in an earlier era may not have survived.” However, she says it is important to “look at C-sections as a tool – like any action that we as physicians do it has good reasons to be used and poor reasons to be used.”
For a brief description of what a C-section is, and an overview of some of the debates related to variations in clinical practice, click here.
Targeted approaches to improve clinical decision making around quality measures
Given the complexity of the factors driving increased C-section rates, experts agree that the approaches taken to address this need to be targeted and driven by data on where these increased rates are being seen.
Sprague says that BORN Registry data is provided back to hospitals and clinicians “so that they have the information they need to make good decisions.” BORN has developed a ‘clinical dashboard’ of six measurements of quality.
The use of these data to tackle variations in C-section rates that may not be related to clinical or patient level factors has been one area highlighted by experts as promising.
Jennifer Blake, CEO of the Society of Obstetricians and Gynaecologists of Canada, points out that there is a “a lot of variation among hospitals and regions, and we need to understand what factors are driving these practices.”
One of the BORN Dashboard measures is the rate of repeat, planned C-sections in low risk women prior to 39 weeks gestation when there are no medical or obstetrical complications. Sprague notes that this indicator was chosen because “there is good evidence that suggests that you shouldn’t do a C-section before 39 weeks” in these low risk women. A full term pregnancy is considered to be between 39 and 40 weeks and six days from the date of a woman’s last menstrual period. The practice is sometimes attributed to scheduling challenges for operating room booking, but evidence points to improved outcomes for mothers and babies if C-sections are scheduled after 39 weeks. Sprague says that simply auditing and reporting this quality measure to hospital administrators and clinicians has been associated with a reduction from 53% in 2012 to 40% currently.
Another quality measure on the BORN dashboard is the rate of labour induction prior to 41 weeks of gestation, which can also increase the chance of cesarean section.
Carol Cameron, a midwife and former head of the birth unit at Markham Stouffville Hospital used these data to support changing scheduling practices at Markham Stouffville Hospital, including not booking requests for inductions without a medical reason prior to 41 weeks. She says “data is king for changing practice and providers really respond to it.” Research has found that this change, and other targeted changes, has led to a 4% decrease in C-sections at the hospital in two years.
Similar initiatives are underway in Alberta. Alberta’s Perinatal Health Program provides hospitals with reports measuring their performance on selected indicators of maternity care, including C-section rates. These rates are categorized by the Robson criteria, which is a way of breaking down C-section rates by the characteristics of a pregnancy.
Nancy Aelicks, a nurse and information coordinator with the perinatal program says that this helps give providers context for the information and “see which Robson groups are making the biggest contribution to C-section rates.”
The application of the Robson criteria and recently published studies comparing C-section rates across Canadian provinces and regions are part of efforts to get a clearer picture of the complex trends driving C-section rates upwards.
Blake suggests more work is needed to understanding this complex interplay of factors – she says “we are only beginning to develop our understanding.”
Blake highlights clinical decision making and individual level ‘human factors’ – including patient and provider points of view as important contributors. “Someone is going to make a decision in the middle of the night that is based on their assessment of all these factors,” she says.
Debates and divergent viewpoints on birth: is it “a disaster waiting to happen?”
Debates around C-sections can be contentious and are often related to differing perceptions of risk, and what constitutes ‘normal’ birth.
Cameron says “if you happen to be someone who believes that birth is a disaster waiting to happen, you are going to tend to jump in quicker.”
Canadian studies comparing rates of interventions (like induction) during labour between midwives and doctors have found fewer interventions among women attending a midwife. However, it should be noted that midwives only provide care to low-risk women with uncomplicated pregnancies. Doctor-attended births in these studies (while adjusted somewhat for patient characteristics) included more high-risk women who may require interventions to ensure safe childbirth.
Cameron also says that “ the midwifery perspective comes from a place of respecting and honouring normal birth – and wanting to support that process – however, this core belief can cut across disciplines and professional groups.”
Another important perspective beyond providers is that of women themselves. Experts suggest that women’s perceptions of birth, including fears of pain or being ‘out of control’, are an important factor informing choices, and increasing C-section rates.
“The perception that pain cannot be controlled in childbirth is wrong and that’s not the way that obstetricians, family doctors or midwives conduct birth,” says Graves.
Blake highlights that ultimately “our patients should feel completely comfortable with how they are approaching their experience with childbirth.”
A 2006 survey of pregnant women in Kingston, Ontario asked about their views on “elective primary C-sections”; that is, C-sections done without an obstetrical indication. Results suggest that a significant number believed that informed choice extended to C-sections, and all women should be provided with the option to choose a C-section.
However, data suggest that C-sections “by request” are a relatively small driver of C-section rates. A 2010 BC study found that these accounted for only about 2% of overall C-sections.
Blake says “you can’t fault women – and I think that we need to understand what the issues are, and the extent to which it is our responsibility (as providers) to address them.”
What does this mean for patients, and providers?
‘Michelle’ is a busy obstetrician at a Canadian hospital with a large maternity care service that delivers over 4,000 babies each year. Reflecting on the numbers of C-sections being done at her hospital, over 1 in 4 births, she acknowledges sometimes challenging conversations with patients about their childbirth expectations, concerns and choices.
“To a lot of people, women and family-centred care means natural, vaginal birth, but if we’re talking about informed consent and shared decision making, my patients occasionally express a clear preference for increased interventions during delivery, including C-sections.” She explains “because events during birth can sometimes be unpredictable, some women wish to assume more control over that process. If I feel that I’ve had a thorough discussion with patients about risks and benefits – it is ultimately their decision.”