Informed Consent – a new era?

Informed Consent – a new era?

CategoryArticles Author Emily Formby QC Date

In a powerful, unanimous, 7 member-decision the Supreme Court has resolved, and possibly revolutionised, the issue of consent.

With a lead judgment by Lord Kerr and Lord Reed, and a consenting but additional judgment by Lady Hale, the Supreme Court has in Montgomery v Lanarkshire Health Board1 determinedly embraced the concept of “informed consent”. At the same time it has struck a further, if not final, blow to the idea of “Doctor knows best”. Medical paternalism – nil: Rights of the patient – 1.


Mrs Montgomery was a highly intelligent woman who was an insulin dependent diabetic and in 1999 was due to give birth to her first child. Mrs Montgomery’s diabetes meant that she was likely to have a baby that was larger than normal, importing a greater risk (accepted to be 9-10%) of shoulder dystocia occurring during birth. Shoulder dystocia (when the baby’s head is delivered but the shoulders are too wide to pass through the mother’s pelvis without medical intervention) is a “a major obstetric emergency associated with a short and long term neonatal and maternal morbidity [and] an associated neonatal mortality”2 There are additional risks to the baby including the risk of brachial plexus injury (running at 0.2% in cases of shoulder dystocia involving diabetic mothers) and cord occlusion resulting in cerebral palsy or death (a risk of less than 0.1%).

Once shoulder dystocia has occurred, management is at best unpleasant – forcing the mother’s knees to her shoulders to widen the pelvic inlet by way of hyperflexion accompanied by attempts to manoeuvre the baby by suprapubic pressure – and at worst involves a surgical procedure whereby the joint uniting the pelvic bone is severed to allow the two halves of the pelvis to be separated to release the baby and allow delivery to occur. If circumstances allow, vaginal birth may be abandoned in favour of an emergency caesarean section. The risk of shoulder dystocia is removed completely if an elective caesarean section is performed3.

Mrs Montgomery’s diabetes made her pregnancy high risk and she was warned that her baby could be large as a result of her condition. She therefore attended fortnightly antenatal appointments under the care of a Dr Dina McLellan for ultrasound monitoring to assess foetal size and growth. At 36 weeks what turned out to be the final ultrasound was performed from which Dr McLellan estimated that the foetal birth weight would be 3.9kg at 38 weeks, albeit there is a 10% margin of error estimating birth weight by ultrasound. Further, it was actually planned that labour would be induced at 38 weeks + 5 days, and Dr McLellan accepted that the extra 5 days would have pushed her estimate to over 4kg. This was of crucial importance because Dr McLellan had planned to offer Mrs Montgomery a caesarean section if the foetal weight was estimated over 4kg because of Mrs Montgomery’s short stature. To compound matters, Dr McLellan decided that Mrs Montgomery should not have a further ultrasound at 38 weeks because she felt Mrs Montgomery was too anxious about the size of her baby and her ability to deliver vaginally.

Albeit she knew of Mrs Montgomery’s fears about vaginal birth, Dr McLellan did not tell Mrs Montgomery about the risks of experiencing mechanical problems during labour nor, in particular, of shoulder dystocia because, so Dr McLellan said, Mrs Montgomery had not asked her “specifically about exact risks” and “since I felt the risk of her baby having a significant enough shoulder dystocia to cause even a nerve palsy or severe hypoxic damage to the baby was low I didn’t raise it with her”. Dr McLellan felt that it was “fair to allow [Mrs Montgomery] to deliver vaginally” and advised her she should be able to do so, with recourse to an emergency caesarean section if needs be. Notwithstanding this decision making process, Dr McLellan accepted in evidence that if Mrs Montgomery had been advised of the risk of shoulder dystocia she would have elected to give birth by caesarean section.

In fact labour was induced but there was a failure to progress and when the baby’s head failed to descend naturally Dr McLellan used forceps. At 5.45pm the baby’s shoulder became impacted at a point when half of his head was outside the perineum. Dr McLellan, who had never been in the situation before, decided to try to complete the delivery by manipulation and pulled the baby’s head with “significant traction” to complete the delivery of the head. To release the shoulders she performed a partially successful symphysiotomy and eventually managed to achieve delivery of a baby boy weighing 4.25kg at 5.57pm.

Unfortunately, in the 12 minutes between the head appearing and delivery, the child’s umbilical cord was completely or partially occluded. As a result, Mrs Montgomery’s son was deprived of oxygen and after birth was diagnosed as suffering from cerebral palsy of a dyskinetic type which affected all four limbs, and a brachial plexus injury resulting in Erb’s palsy. If he had been born by elective caesarean section, Mrs Montgomery’s son would have been born uninjured.

At first instance

The Lord Ordinary rejected the claim because, following the approach taken in the Sidaway v Board of Governors of the Bethlem Royal Hospital and the Maudsley Hospital4 case, he decided that whether a doctor’s omission to warn a patient of inherent risks of proposed treatment constituted a breach of the duty of care was normally to be determined by the application of the Bolam test. It therefore depended on whether the omission was accepted as proper by a responsible body of medical opinion. He applied Lord Bridge’s formulation that if the patient raised specific questions in respect of the risks associated with treatment the medic concerned was duty-bound to answer such questions fully and truthfully. As Mrs Montgomery had not raised any specific questions around the risks associated with mechanical problems during birth, and because the defendant’s expert considered that Dr McLellan’s failure to warn was reasonable given that the risks of a serious outcome for the baby were so small, the claim failed at first instance and on appeal to the Inner House.

In England and Wales, unlike Scotland, the Sidaway position had been softened by a greater emphasis on Lord Bridge’s approach as articulated by Lord Woolf MR in Pearce v United Bristol Healthcare NHS Trust5 noting that, “if there is a significant risk which would affect the judgment of a reasonable patient, then it is the responsibility of a doctor to inform the patient of that significant risk” so as to enable the patient to take a more informed view. Nonetheless, the assessment of risk and the determination of information delivery still firmly lay in the hands of the doctors, assessed as reasonable by viewing the practice of other doctors.

Before the Supreme Court

When the matter came before the Supreme Court, they took a different view. Lords Kerr and Reed recognised that the unqualified doctor-centric approach to consent set out by Lord Diplock in the House of Lords in Sidaway some 30 years ago was out of date. They explicitly recognised (at para 81) that social and legal developments now point away from a model of the relationship between the doctor and the patient based on medical paternalism, and upon the patient being entirely dependent on information provided by the doctor. Instead, patients are to be considered, as far as possible, as adults able to understand that medical treatment comes with risk and uncertain outcomes and who must accept responsibility for taking those risks which might affect their life or future well-being. Moreover, it was explicitly recognised that most patients now have access to a number of research avenues other than their medical practitioner – a first for Dr Google, perhaps. It was also recognised that patients can make a decision in which non-medical elements play a part but which is no less sensible or cogent a decision according to that patient’s value systems.

If patients are to take on this decision-making burden, there must be a duty on the part of doctors to take reasonable care to ensure that a patient is aware of material risks of injury that are inherent in treatment. Accordingly, a doctor’s function in advising of the risks associated with different treatment options is no longer to be regarded as a straightforward exercise of medical skill and therefore responsibility for determining the nature and extent of a person’s rights in respect of that advice cannot be assessed on the Bolam test by looking at what other medical professionals do. Responsibility for determining the nature and extent of a person’s rights rests with the courts (see para 82 – 84).

Lords Kerr and Reed acknowledged that some patients may decide that they do not wish to be informed of the risks of injury they face with any given treatment and that a doctor is not obliged to discuss risks with this type of patient. Further there may still be instances where the doctor is not required to discuss risks with their patient if disclosure of a risk may be detrimental to a patient’s health, but this “therapeutic exception” is not the basis of a general rule.

In the end, their Lordships analysis of the correct position is in fact substantially the same as that adopted by Lord Scarman in Sidaway. In relation to risks of injury and consent and in the absence of the “therapeutic exception”, an adult person of sound mind is entitled to decide which, if any, of the available forms of treatment they wish to undergo and their consent must be obtained before treatment interfering with bodily integrity is undertaken. When discussing risk, a doctor is therefore under a duty to take reasonable care to ensure the patient is aware of any material risks involved in any recommended treatment and of any reasonable alternative or variant to that treatment. This duty was not likely to be discharged by bombarding a patient with technical information, nor by routinely demanding a signature on a consent form but could be met with an appropriate dialogue during which comprehensible information was shared.

Further, that materiality of risk is to be assessed by a judgment as to whether, in the circumstances of the case, a reasonable person in the patient’s position would be likely to attach significance to the risk, or whether the doctor is or should be aware that the particular patient would be likely to attach significance to it; it cannot be reduced to a discussion of mere percentages (see paras 87 – 89).

Insofar as concerns may be raised against this approach, Lord Kerr and Lord Reed give them relatively short shrift. Their view was that if practice must change, so be it. Other jurisdictions have managed and “respect for the dignity of patients requires no less”.

The consequence of this analysis was the clear finding that Mrs Montgomery should have been advised of the risk of shoulder dystocia and of the potential consequences of that complication. Dr McLellan’s position that she did not warn Mrs Montgomery of these risks because most women in Mrs Montgomery’s situation would immediately have elected a delivery by caesarean section received fierce criticism from Lady Hale who said, “whatever Dr McLellan may have had in mind, this does not look like a purely medical judgement. It looks like a judgement that vaginal delivery is in some way morally preferable to a caesarean section: so much that it justifies depriving the pregnant woman of the information needed for her to make a free choice in the matter.”


On the one hand, this judgment finally confirms what has been happening by way of “mission creep” in the lower courts for some time. The struggle to pull issues of consent and risk assessment from the Diplockian view in Sidaway so as to more accurately reflect the reality of modern interaction between doctor and patient has finally been clearly articulated. The days of trying to achieve it in practice through adopting the gloss provided by Lord Woolf in the case of Pearce v United Bristol Healthcare NHS Trust6 may now be at an end.

This decision of the Supreme Court brings much-needed and welcome clarity to the issue of consent and clearly places the onus on the doctor to perform an enabling role with a patient – inform them of risks and outcomes, support the decision making process and allow a patient to make a meaningful consent to any procedure.

One would expect digestion of this judgment to lead to significant changes being made in the consent process given the need to place the patient at the centre of the decision making process, with discussion of risks tailored in each case to the needs and concerns of the particular patient. It will perhaps be most likely to affect obstetric cases when the development of a baby can lead to changes in birthing plans or ideas throughout pregnancy and into labour. Consent will need to be a dynamic and on-going process.

On an immediate level one wonders how the over- stretched NHS will cope if the practice of holding a pre-operative clinic where patients are prepped, given a leaflet or two, consented and written-up for prescriptions in a nurse-led clinic a week before a straight forward day surgery must now be abandoned in favour of a more tailor made consent process. At the very least medical practitioners can no longer rely on their own assessment of “needs to know” basis consent.

This article was written by Emily Formby and was first published as part of the Personal Injury Newsletter – April 2015.

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1[2015] UKSC 11
2 According to an expert witness who gave evidence in the proceedings.
3 A procedure which carries its own potential risks and complications.
4 [1985] AC 871
5 [1999] PIQR P53
6 [1999] PIQR P53, CA

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