Evidence for the knee-jerk effect in maternity care

medium_9468151425Midwives, doctors and others working in maternity care are all too aware that adverse outcomes tend to have a lasting effect, even (and perhaps sometimes especially) when they are unpredictable or unpreventable.  But I am just not referring to the impact they have on the families and caregivers involved, which is huge and deserving of much discussion.  Events which ended in tragedy or a near-miss scenario are also often the catalyst for significant changes in approach or policy, most often involving a narrowing of the boundaries of what is considered OK, or normal.

I have seen this time and time again in different countries and areas of care.

In my experience, it is most likely to happen where two or more similar adverse events occur in a unit in a relatively short time period. When this happens, it is awful, but statistically not that unlikely in centralised maternity services which mean than thousands of women give birth in a particular unit or Trust every year.

But I have also seen changes in approach and/or policy after just one adverse outcome.

The response tends to be something along the lines of: “right, we had a bad outcome after a woman had been in labour for twelve hours / planned a VBAC / got in the pool (or whatever was ever-so-slightly unusual about the situation). We must learn from this and limit all labours to eleven hours / caesarean section / land, so nothing bad happens again.”

This is irrespective of whether there is any evidence that such a limitation would have saved or prevented harm coming to that particular mother or baby. Or whether it would would save or prevent harm coming to any future mothers or babies in the same situation. It’s also usually irrespective of what the effects or downsides of such a policy might be on others.

It is understandable that we want to do something, but what we do may lead to more harm than good.

I am certain that others will also have witnessed this kind of knee-jerk reaction to an adverse event.

Such reactions can mean that all of the decision-making processes that have been carefully built up over time in order to ensure that policies are collective and evidence-based are simply ignored. An instant ban on certain practices may be brought in, often to the dismay of both staff and women.

It is not always so obvious though.

The comfort level of individual practitioners may temporarily shift after a poor outcome. This can lead to a lower tolerance for uncertainty or for particular situations.

Ideally, we need to respond to this with concern, and by providing safe spaces for practitioners to work through their thoughts and feelings.

These days, however, midwives and doctors who have experienced an adverse event are more likely to be bombarded with paperwork, risk assessments and questions than TLC.

There isn’t a lot of literature on this phenomenon though. So I was really interested to read a study by Riddell et al (2014) which was published in Obstetrics and Gynecology.  The researchers looked at the effect of uterine rupture on a hospital’s future rate of vaginal birth after caesarean (VBAC).  Using data from the US Nationwide Inpatient Sample, they looked at changes in VBAC rates, trial of labour (sic) rates and VBAC success rates over time.

Their findings were significant:

medium_6848014309‘Before the occurrence of a severe uterine rupture, there were an estimated 60 successful vaginal deliveries for every 100 women with a previous cesarean delivery who entered labor. In the month after the rupture, the trial of labor success rate decreased by an estimated 25 cases per 1,000 labors (95% confidence interval [CI] 6–44/1,000, P=.01) before returning to baseline. The percentage of women with a previous cesarean delivery who attempted vaginal delivery did not significantly change after the rupture. Overall, there were 17 more cesarean deliveries per 1,000 women with a previous cesarean delivery (95% CI 4–31/1,000, P=.01) in the month after the uterine rupture.’ (Riddell et al 2014: 1175)

This evidences that just as many women were still wanting VBACs, and were starting out in labour hoping and intending to have a VBAC, but fewer of them achieved this after another local woman had recently experienced uterine rupture.  Riddell et al (2014) conclude – though of course this is informed speculation, as research can only tell us that something happened, not why it happened – that ‘the decrease in the trial of labor success rate after a recent uterine rupture is likely the result of short-term changes in risk evaluation’.

Knowing this doesn’t necessarily make things any better for the women who were more likely to have been told they needed a caesarean section soon after another woman had experienced a uterine rupture.

But if I have learned one thing about birth-related decision-making from my years of studying this area, it is that it is rarely as rational as some people claim.

Human factors are always present.

If we could acknowledge that, then perhaps we could move towards a more honest approach. In which we acknowledge our humanity, concede that decision-making is just as much an art as a science, and admit that there are many things we do not know.


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Riddell C, Kaufman JS, Hutcheon, JA et al (2014). Effect of Uterine Rupture on a Hospital’s Future Rate of Vaginal Birth After Cesarean Delivery.  Obstetrics & Gynecology 124(6): 1175-81.


photo credits: pathway by `James Wheeler and caesarean by Pieter v Marion via photopin cc and cc