The Emperor’s new clothes: the politics of birth research — Sheena Byrom

In Christian Andersen’s tale of the ’s clothes no one dares to say they don’t see a suit of clothes on him for fear they be seen as stupid and incompetent. It takes the cry from a small , “but he isn’t wearing anything at ”, to identifying the farce being carried out.

Sometimes papers are put out with misleading releases and political agendas that unquestioned by a media hungry for controversy and the sensational headline. In this blog we will identify the Emperor in the form of the recent New Zealand paper (NZ) published by (2016), titled A of -Led and -Led of Care and Their to Adverse Fetal and Neonatal Outcomes: A Retrospective Cohort Study in New Zealand.  The Wernham paper caused consternation around the globe with waving it in triumph pretending the Emperor had a magnificent outfit on while midwives scrambled to understand what was happening, amidst the crowd, “but he isn’t wearing anything at all.”  

How did something that was fairly low level scientific evidence get more attention, and to such questioning of the of care, than 15 randomised controlled trials and a (CSR) on this issue?

Just a reminder about the Level 1 evidence of continuity of midwifery from over 17,000 randomised in 15 separate RCTs:

“This suggests that women who received midwife-led continuity models of care were less likely to experience intervention and more likely to be satisfied with their care with at least comparable adverse outcomes for women or their infants than women who received models of care. Further research is needed to explore findings of fewer preterm births and fewer fetal deaths less than weeks, and all fetal loss/neonatal associated with midwife-led continuity models of care.”

 How did we ever think the Emperor had new clothes?

The alert in this recent saga is the that came out from the ’s university, strictly embargoed beforehand to excite the ‘crowd’ awaiting the emperors arrival. The media release revealed the first in the authors’ and was the ultimate hook for the media:

“Mothers using autonomously practising midwives throughout their and are more likely to have adverse outcomes for their newborns than those who use obstetricians, according to a retrospective study of nearly a quarter million born in New Zealand published in PLOS by Wernham of , New Zealand, and colleagues.”

Firstly, this study was never about midwifery care during childbirth, or pregnancy for that matter. Midwives also after women cared for by private obstetricians so this care is never just about just as it is never just about midwifery care. Secondly, was no statistical difference in perinatal mortality. would have hardly known this from the . Thirdly, the authors were clearly dredging when they combined Intrauterine hypoxia, related asphyxia and neonatal encephalopathy in order to get a highly significant outcome. adverse and small numbers were sensationalised in the media release (“55 percent lower of birth related asphyxia, 39 percent lower of neonatal encephalopathy, and 48 percent lower of a low Apgar score at five minute after delivery”). Neonatal encephalopathy occurs 1-2 in 1000 births and is a rare event. Presented this way makes it so dramatic and it takes only one or two cases to change the outcome.

Why the Emperor is actually naked

The authors were unable to look at actual care during childbirth because they don’t appear to have this data, so they took of care at booking and then misled the media and public that this was an indication of care at birth, when it was not. The problem with this is while all women who book with private obstetricians will remain under the care of private obstetricians from booking to birth, between 30-35% of women under midwifery care will be referred during pregnancy to a . Despite this all outcomes (only adverse perinatal ones) in the paper are reported as due to midwifery care, when they are clearly not.

One could argue that the randomised controlled trials (RCTs) of continuity of midwifery care reported in the use a similar method – that is model of care on booking and intention to treat analysis. , the difference is randomisation reduces selection bias and the study groups should be as similar as possible at the outset so the researchers can isolate and quantify the effect of the intervention they are studying (in this case midwife or medical care). In a RCT you can see what care women got and you would also know the mode of birth and maternal outcomes, which are not reported in this study. RCT’s can be used to change practice but lower level evidence should not; yet that has not stopped groups such as the calling for this in .

The NZ study had several concerning limitations that were not adequately considered in the unfolding :

1.     One of the most significant findings of the CSR of continuity of midwifery care was the 24% reduction in preterm birth under midwifery care. There was also a significant reduction in perinatal mortality. Only women over 37 weeks were included in the recent NZ study, so there was no to see whether this effect was seen in this study.

2.     Not only are of term outcomes but there were a large number of missing Apgar scores and this was greater for women who booked with obstetricians.

3.     The of women more than 42 weeks, which were seen in larger numbers in the midwife booked group and are more likely to have stillbirths associated with prolonged pregnancies, is concerning. If the authors took 37 weeks gestation as a -off to exclude preterm birth (higher risk), why not take 41+6 to exclude the higher risk post-term pregnancies. It would have been very interesting to know how many adverse events were seen in the post-term group. Women choosing midwifery care are more likely to not want to be induced and to go over 42 weeks, as is seen in this study.

4.     The inability to separate antepartum stillbirth from intrapartum stillbirth is critical in trying to assess the impact of birth provider on outcomes and this could not be done, despite the suggesting it would be.

5.     In the study protocol published with the paper neonatal nursery admissions were examined but not reported. When we look at the ’s Master’s thesis where this is available, more neonatal admissions are reported for babies born to women who booked with private obstetricians. This was not reported in this paper. One has to , why?

6.     In the first author’s Master’s thesis (where this study originally came from), substantially lower rates of caesarean section (22% vs 32.9%) and instrumental birth rates (9% vs 12.3%) are reported for women who booked with midwives, leading to significantly less maternal morbidity. Again this was not reported, giving a very one-sided considering the authors are virtually questioning the entire NZ maternity system.

7.     There appears to be quite a bit of missing data in this study and it is unclear how this was dealt with in the analysis.

8.     Many socio demographic variables are not accounted for (e.g. and use), and others such as smoking are notoriously underreported. Midwives to look after women with greater socio demographic disadvantage and mental issues. None of this is adjusted for.

9.     Other medical complications that following booking, such as gestational , pre-eclampsia, etc are not accounted for and be increased in women who book with midwives due to ethnicity factors, etc.

10.  Rurality and birth place were not taken into consideration, limiting the usefulness of this study to make targeted changes than slamming the entire N Z maternity system.

11.  There is no difference in PMR between Australia and NZ despite the fact that 30% of care in Australia is by private obstetricians whilst in NZ around 90% of women have a midwife as a lead care provider.

12.  A previous NZ paper that also hit the media headlines in recent times, purporting to show the risk of perinatal death was higher when midwives were in their first year following graduation, has recently been questioned by the who have been unable to replicate the study. This is worrying.

13.  of low risk women in NSW who had a birth in a private under private obstetric care with low risk women who had a birth in a public with midwife/medical care we found greater morbidity for women giving birth in a private obstetric model of care.

The one highlight in this whole saga has been the united of the midwives in NZ by the , The , , and bodies around the .

The political fallout from this paper has been extraordinary, for it actually tells very little. No practice changes could ever be made based on this study. The Emperor may have no clothes, but the delusion has been maintained by a misleading media release, politically motivated reporting of findings by the authors, a sensing blood in the and wanting sensational headlines, and obstetricians determined to the advances made by the of midwifery back to the ‘good days’ when they were compliant handmaidens. 

#ENOUGH



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