With acknowledgement to Dr Nadine Edwards and Dr Gosia Stach for introducing me to this particular logical fallacy.
I consider obstetrics as a way of knowing and doing, an epistemological paradigm. Birth technology is valued within the obstetric paradigm. Within the term birth technology, I include things like ultrasound, induction of labour, partograms, and of course the CTG. The existence of any particular birth technology and the knowledge and processes related to it are typically considered to possess a self-evident truth. If the technology exists, then it does so because it must work. Otherwise, why would it exist and why would clinicians be using it?
There is a circular argument which sits at the heart of the beliefs about birth technology and it consists of three related lines of logic.
The first line of logic states that if the technology is used and the anticipated risk the technology was used to prevent doesn’t happen, then that is because the technology works. Given that the actual risk for most of the outcomes we are trying to prevent is low, this means that most of the time beliefs in the use of the technology are reinforced.
You might then think that if the anticipated risk does occur, then this would undermine the belief that the technology works. That’s actually not what happens, as experiencing the undesired outcome is also used to reinforce belief in the technology. How does that happen exactly?
The second line of logic operates in this manner: if the technology was used and the anticipated risk does occur, then there will be a search for the individual responsible for this outcome. The two most likely people to be held responsible for this are the woman herself (because her body was simply “too risky”, or because she resisted the ideal application of the technology), and the woman’s midwife (because they lacked the knowledge to, or wilfully chose not to, apply the technology in the perfect manner). Sometimes, but less often, an obstetrician might be held to account. If this investigation identifies someone who can be blamed for the outcome, then this serves as proof that the technology still works.
The third line of logic considers that if the technology was used and the anticipated risk occurred, but following a thorough interrogation of the facts, no individual can be held to blame, then the outcome was simply unavoidable and could never have been prevented by the technology. The technology is still held to be effective, but just not in this isolated case.
What does this look like for CTG monitoring?
As a consequence of these three lines of logic, the misapprehension that CTG monitoring technology is effective in preventing poor perinatal outcomes persists and is strengthened. First, perinatal mortality and severe neurological occur infrequently, so the vast majority of women who are monitored by CTG technology will not experience either outcome. The lower the incidence of mortality and neurological injury, the more effective CTG monitoring appears to be. Expansion of the use of CTG monitoring to women with lower risks can generate the appearance that CTG monitoring improves outcomes.
Second, if CTG monitoring is used and a poor perinatal outcome occurs, it will not be considered that CTG monitoring was never able to prevent the problem in the first instance. A search for a scapegoat will ensue. Risk management processes such as root cause analyses are typically used. This particular line of thinking is very powerful in capitalist healthcare systems with strong governance. A market for educational activities is easily created and maintained. The need for policy development and surveillance systems to ensure clinicians are held accountable to these policies appears as a self-evident truth. These activities generate authority and income. Ironically, this authority and profitability is best maintained when there is a steady but infrequent trickle of poor outcomes, as this supports the argument that more CTG education and better governance is still required.
And third, if poor outcomes occur, and the CTG use was in accordance with policy, then it is always possible to dismiss the outcome as unpreventable, and an example of the limits of the technology. Ongoing rates of poor outcomes when CTG monitoring has been used according to best practice recommendations provides stimulus for the development of further fetal monitoring technology. Central fetal monitoring, computer interpretation of the CTG, and ST segment analysis are examples of this. A culture that values innovation, technology, and profitability will see this as a great opportunity. There is seductive logic in the belief that adding another “state of the art” technology solution to CTG monitoring will finally provide the solution we seek.
How do we break out of this cycle?
Research permits us to see whether a birth technology actually improves outcomes, or alternately whether it generates new problems. It is vital that appropriately designed research is undertaken before the next new thing gets added into the mix. It is important that research asks women and clinicians about their experiences with birth technology, rather than simply relying only on the sorts of outcomes we traditionally measure (death, Apgar scores, mode of birth for example). Doing so generates a richer understanding of what happens when such technologies are used.
It is also important that we use research to step back and assess birth technologies that have been under-investigated. We then need to commit to using the findings of that research to underpin our clinical practice and begin the challenging work of removing ineffective technology, like CTG monitoring, from maternity care.