Friday 23 January 2009

whose risk?

When my Kent Midwifery Practice blog colleague Eleanor told me the story of her client and their perception of risk, I thought it a really good subject for a new post. Then I was approached by a midwife who is researching the subject and looking at it from a midwife's perception and how she considers risk. I have now agreed to be part of her research and have been thinking about it a lot myself.

Risk and how, as humans, we view risk has been the subject of many studies around countless topics and is a subjective judgement made depending on the characteristics and severity of a risk. The influence of the media on the perception of risk is a clear demonstration of how something which is very low risk but is considered an emotive subject could actually cause a red herring effect. That is demonstrated by the whole "stranger danger " subject , making parents almost paranoid to let their children out of sight as they think the risk is too great.

What could be a more emotive subject to a woman than the baby she is carrying? Given a choice all women would eliminate any risk from pregnancy and childbirth but especially any risk to her child. I cannot think of one mother who I have cared for who given the choice of saving her unborn or new baby's life or taking her own life, would not have prioritised her baby.

One mother said to me "Virginia they could have taken my arm if my baby was in trouble". This woman was recovering from a nasty infected episiotomy which was performed in haste and panic by medical staff who believed her baby's heart had stopped abruptly prior to his birth. However what had really happened was the heart monitor had stopped abruptly.

So thinking about that I considered how mothers think about risk. Can we consider birth to ever be without risk? No, we cannot, but that is not to say birth is a "risky business" unless we consider that life is a risky business or driving our car is a risky business. Both those things we do on a daily basis without giving it any thought whatsoever. Who makes the decision on what is an acceptable risk around all the issues of childbirth and what is not? It should be the mother of course, but it rarely is.

We are just about there in the UK with regards to the safety of homebirth. Studies which demonstrate homebirth as a safe option for most women have just about been accepted by our medical colleagues [1, 2 - refs below]. Except for the most obstinate practitioners who refuse to keep updated despite the evidence having been around for a decade or more, most obstetricians will support a homebirth as long as a woman does not have any risk factors.

Yet all women, even the ones considered as low-risk, have risk factors - for a low-risk woman has a 2.7% chance of an unexpected complication occurring in labour [3] A complication that may need urgent assistance and delay could result in the problem becoming compounded. That is considered a low risk.

Let's consider a woman who has a nuchal scan to screen for a baby to be affected with trisomy 21 (Downs Syndrome). She has a 1:250 or 0.4% risk of her baby being affected and is told that is low. Who made that decision? Some women would consider it a no-risk situation; indeed some do and refuse to have the screen at all.

The number of babies that die unexpectedly following a prolonged pregnancy further than 42 weeks is approximately 2:1000 or 0.2% [4.] but that is considered so high a risk that 20% of UK women have labour induced [5], and that number of women are included in the 1:4 or 25% of women that make up the caesarean section rate in the UK.

When she has a section, the woman faces up to sixteen times times the risk of death, and ten times the risk of emergency hysterectomy, than a woman giving birth vaginally [6]. Yet a woman who plans a homebirth roughly halves her risk of ending up with a caesarean and all the risks it involves, compared to someone of the same risk level planning a hospital birth [2] She also roughly halves her risk of her baby being born in poor condition [2] - so why are some risks considered more acceptable to take than others?

Once the woman has had the caesarean section she is told she now has a 1:200 or 0.5% risk of a scar dehiscence which is considered high-risk and the medical profesion would be highly unlikely to support a decision for a home birth. However that number includes induced and augmented labour and benign dehiscence that is seen at elective caesarean section - most studies find a greatly reduced risk of rupture in spontaneous-onset labours which are not augmented with oxytocin. Maybe if figures were quoted for both actively-managed VBAC labours and for spontaneous, unaugmented VBAC labours, the risk perception would change and the place of birth and labour management would be more open to discussion

The most bizarre I think in the calculation of risk is the 1:10,000 or 0.01% of vitamin K deficiency bleeding. It is recommended that mothers agree to injecting a substance into all newborns because they are, apparently, fundamentally flawed and do not have normal levels of vitamin K at birth. Who says what is abnormal and what is that abnormality measured against? Sara Wickham considers that statistics for Vitamin K are the same risk as wearing a hard hat every time you walk outside your front door in case a roof slate falls off and hits you on the head. [ 7.] I think maybe a little more research is needed in relation to cost-effectiveness if that is the case. There has never been a follow-up study on children whose parents refused vit K. There could be a huge saving for our cash-strapped health service if the Vitamin K bill was reduced.

Key findings from major studies [8]such as Starr, were that the experts are not necessarily any better at estimating risk than lay people. Experts were often overconfident in the exactness of their estimates. I accept that the Starr study may be a very old piece of research but it surely is very relevant in our modern nanny-like society. Starr also found that people will accept risks 1,000 greater if they are voluntary than if they are involuntary. Information if presented in an unbiased way will assist women in their individual perception of risk and may even play a part in women taking responsibility for their choices. It may even reduce the ever growing litigation bill for medical negligence.....

At Kent Midwifery Practice we are clear that the mother is the only person who can decide what risks are acceptable for her family. It is not acceptable for professionals to say that lay people should not make their own decisions because they think that only they, the professionals, understand risk; nobody will care more about the risk to an unborn child than its mother.

The job of the midwife, whether independent or NHS, is to give the woman the information she needs, and to help her to understand how different risks apply to her. We all take risks; it is the pregnant women who should decide which risks she will take.

REFERENCES[1] British Medical Journal No 7068 Vol 313, 23 November 1996[2] Home Births - The report of the 1994 Confidential Enquiry by the National Birthday Trust Fundpub. The Parthenon Publishing Group, 1997. [3] Effective Care in Pregnancy and Childbirth, eds. Enkin, Keirse,Renfrew & Neilsen, 3rd Edition (published 2000, OUP), p360[1a] Chapter 38, section 6. "The probability of requiring an emergency CS for other acute conditions (fetal distress, cord prolapse or antepartum haemorrhage) in any woman giving birth is approximately 2.7%"]. [4] Menticoglou SM and Hall PF. Routine induction of labour at 41 weeks gestation: nonsensus consensus. BJOG 2002;109:485-91 [5] NICE Guidelines on Induction of Labour, July 2008, S1. : "In 2004–05, 19.8% of all deliveries in the UK were induced." [6] BMJ. 1998 Aug 15;317(7156):463-5. Should doctors perform an elective caesarean section on request? Maternal choice alone should not determine method of delivery. Amu O, Rajendran S, Bolaji II. [7] Wickham, S, Vitamin K - A flaw in the blueprint?, Midwifery Today, 2000; 56: 39-41. [8] Social Benefits versus Social Risks by Chauncey Starr, Science ,1969 .
2009/1/23 Virginia Howes <virginia@kentmidwiferypractice.co.uk>