Aidan O’Brien discusses Montgomery v Lanarkshire Health Board [2015] UKSC 11

Published: 15/09/2015 | News

Aidan discusses the case of Montgomery v Lanarkshire Health Board [2015] UKSC 11 and explores the legal issues surrounding  informed consent to medical treatment.

Factual Background

In October 1999, Nadine Montgomery gave birth to her first child, who sustained severe disabilities as a consequence of shoulder dystocia during his birth. Her treating obstetrician, Dr Dina McLellan, had not informed Nadine of the 9-10% risk of this complication arising.

Nadine was of small stature and suffered from diabetes mellitus. Women with this condition are likely to have larger than average children, with their weight particularly concentrated in the shoulders. During a normal vaginal birth, a baby’s head will descend the birth canal and the rest of the body will thereafter follow. Shoulder dystocia occurs when the head descends the canal but the baby’s shoulders prevent it passing through the mother’s pelvis without medical intervention. In around 0.1% of cases, shoulder dystocia will occlude the umbilical cord and cause the baby to suffer prolonged hypoxia. Unfortunately this risk materialised in the present case and Nadine’s son was starved of oxygen for around 12 minutes during his birth.

The principle claim in Montgomery related to Dr McLellan’s failure to warn Nadine about this risk. It was argued that if she had been properly informed she would have elected to undergo a caesarean section (obviating the risk entirely).

The evidence of Dr McLellan was that she did not discuss this complication with diabetic women given that they would invariably elect for a caesarean section and it was ‘not in the maternal interests for women to have caesarean sections’.

Legal Analysis

The Supreme Court’s determination, in favour of Nadine Montgomery, marks a significant shift in the test to be applied when considering whether a patient has given consent to medical treatment.

The House of Lords decision of Sidaway v Board of Governors of the Bethlem Royal Hospital and the Maudsley Hospital [1985] AC 871 no longer holds sway. Practitioners need to be alive to the fact that not only has the requirement for informed consent been formally recognised, but also that Sidaway did not reflect the standard of care required at the time of Montgomery’s care.
Previously, Sidaway dictated that it was a matter for clinicians to judge how much information was to be disclosed to a patient. Provided the doctor explained the risks of a given treatment – to the extent that it accorded with a responsible body of medical opinion – liability would not attach (the Bolam test).

Following Montgomery, the law now generally requires that a doctor must take ‘reasonable care to ensure that the patient is aware of any material risks involved in any recommended treatment, and of any reasonable alternative or variant treatments.’

‘Materiality’ is to be judged by reference to the individual circumstances of the case and whether 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. This requires consideration of the patient as an individual – a risk that is ‘material’ for one individual may not be so for another – and thereby requires a bespoke consent process.

It also follows that a doctor’s advisory role is not to be regarded as solely an exercise of medical skill. A patient is entitled to decide the risks that they are willing to run (a decision which may be influenced by non-medical considerations) and responsibility for determining the nature and extent of a person’s rights rests with the courts, not with the medical professions.

There are, however, three exceptions to the general requirement to inform:

  • If a patient tells the doctor that he or she would prefer not to know the risks.
  • When the doctor reasonably considers that disclosure of a risk would be seriously detrimental to the patient’s health (this exception should not be abused to subvert the principle of informed consent).
  • In circumstances of necessity, as for example where the patient requires treatment urgently but is unconscious or otherwise unable to make a decision.

Applying these principles to Mrs Montgomery’s case, it is clear that she did have the right to be advised of the risk of shoulder dystocia, and she had the right to make her own decision on what risks she was prepared to undertake in terms of the delivery. The court accepted her evidence that she would have opted for a caesarean section if properly advised. Damages of £5.25 million were therefore awarded.

In a scathing reproach of Dr McLellan’s conduct, Lady Hale stated:

‘Whatever Dr McLellan may have had in mind, this does not look like a purely medical judgment. It looks like a judgment that vaginal delivery is in some way morally preferable to a caesarean section: so much so that it justifies depriving the pregnant woman of the information needed for her to make a free choice in the matter…

A patient is entitled to take into account her own values, her own assessment of the comparative merits of giving birth in the “natural” and traditional way and of giving birth by caesarean section, whatever medical opinion may say, alongside the medical evaluation of the risks to herself and her baby…

The medical profession must respect her choice, unless she lacks the legal capacity to decide.’ [113]


As practitioners in this field will appreciate, whilst the decision of Sidaway remained binding, the English courts had gradually begun to adopt the principle of informed consent (see Pearce v United Bristol Healthcare and Chester v Afshar). In fact, guidance issued by the General Medical Council Guidance has demanded a much more patient focused consent process than prescribed by Sidaway in recent years.

The Supreme Court has now authoritatively killed off the last vestiges of the old clinician-centric approach and confirmed that informed consent plays a central role in English law (effectively endorsing the dissenting judgment of Lord Scarman in Sidaway.

In giving judgment, Lord Kerr remarked that:

‘[Since Sidaway] …patients are now widely regarded as persons holding rights, rather than as the passive recipients of the care of the medical profession. They are also widely treated as consumers exercising choices… The idea that patients were medically uninformed and incapable of understanding medical matters was always a questionable generalisation…’ [74-75].

The law of consent now formally treats patients, so far as possible, as adults who are capable of understanding that medical treatment is uncertain of success and may involve risks, accepting responsibility for the taking of risks affecting their own lives, and living with the consequences of their choices.

Aidan specialises in Medical Law – for more information about his practice please click here.

Author: Aidan O'Brien Farrars (