The Supreme Court handed down a unanimous decision in the case of Montgomery v Lanarkshire Health Board [2015] UKSC 11 on 11 March 2015.

The case concerned an alleged failure to advise a diabetic mother of the risks of encountering shoulder dystocia during labour, and to offer caesarean section to avoid injury to the child and/or mother. It was accepted that the risk of shoulder dystocia in the mother's case was in the region of 9%. The Supreme Court concluded that the correct legal test to apply was not what a reasonable obstetrician would have advised a patient in these circumstances, based on the principles laid down in Bolam v Friern Hospital [1957] 1 WLR 582, but instead the correct test was one of patient autonomy. Please click here to read our previous article on Montgomery.

Based on the above, it has been suggested by many advisors, both for the Claimant and Defendants, that patients must be informed of all risks in respect of any treatment option in order to provide informed consent. Some have even gone so far as to suggest that the consenting process should always be video recorded. In our view, this is clearly not practical and indeed this is not our interpretation of the judgment given that the Court specifically states that: "The doctor is however entitled to withhold from the patient information as to a risk if he reasonably considers that its disclosure would be seriously detrimental to the patient's health. The doctor is alsoexcused from conferring with the patient in circumstances of necessity, as for example where the patient requires treatment urgently but is unconscious or otherwise unable to make a decision." In addition, the Court specifically states that the duty is to inform of any material risk.

The question therefore is what a material risk is and more importantly how do you determine what is material to a specific patient?

In the case of A v East Kent Hospitals University NHS Foundation Trust [2015] EWCH 1038 (QB), Mr Justice Dingemans set out his interpretation of material risk as defined by the Supreme Court. The case is a wrongful birth claim where A sought damages for the costs associated with raising a disabled child.

A had attempted to conceive naturally which had resulted in one pregnancy, which unfortunately spontaneously miscarried at eight weeks. A and her partner paid privately for a DNA fragmentation and sperm aneuploidy test. The results showed that the DNA test had been carried out on chromosomes 13, 18 and 21 with no abnormality noted. However, A was informed that only the three most common chromosome abnormalities had been tested, so there was a possibility that abnormalities could be found in the other 43 chromosomes. Knowing this, A proceeded to a cycle of IVF via ICSI, which was successful.

Nuchal translucency and serum biochemistry tests in the first trimester confirmed that the foetus was not at an increased risk of genetic abnormalities for trisomies with chromosome 13, 18 and 21. The risks were 1:37,891 for a trisomy with chromosomes 13 and 18, and 1:1753 for a trisomy with chromosome 21. A was happy to proceed with the pregnancy with these known risks as it was her evidence that they represented "no risk at all".

At the anomaly scan at 21 weeks gestation, no structural abnormalities were noted, but the fetus was recorded as growing along the 5th centile. The fetus remained constitutionally small throughout the pregnancy and on review by a Consultant; A was advised that the most likely cause for the restricted growth was placental insufficiency. Following delivery, the child was found to be suffering from an unbalanced translocation of chromosomes 4 and 11 and is significantly disabled.

It was the evidence of A that had she known that a possible cause of fetal growth restriction was chromosome abnormality, she would have undergone amniocentesis. On discovering the unbalanced translocation she would have terminated the pregnancy at either 32 weeks or 35 weeks gestation.

The issues to be determined by the Court were as follows:

  1. Should A have been informed of the possibility that chromosome abnormality was causing fetal growth restriction
  2. If so, would A have proceeded to amniocentesis in the second trimester
  3. If amniocentesis had been carried out, would A have terminated the pregnancy at 32 or 35 weeks gestation?

1. Should A have been informed of the possibility of chromosome abnormality?

A relied on the fact that she had undertaken DNA fragmentation testing and first trimester testing to support her position that she did not want a disabled child. In addition, she relied on the judgment of Montgomery stating that a child with disability was a material risk to her and had she known that there was a possibility, however small; she would have wanted to know about it. Her experts confirmed that the risk of chromosome abnormality in this pregnancy was more than 1% and more likely in the order of 3%. It was argued by A that a risk of more than 1% in such circumstances was material and therefore A had the right to be informed of that risk.

The Court accepted the evidence of the Defendant trust that chromosome abnormality of the type suffered by A's child was so rare that the actual risk was in the order of 0.5%. The Court accepted that placental dysfunction was the likely cause of fetal growth restriction (which was in fact accepted by A's experts) and it was reasonable not to advise A of a "theoretical", "negligible" or background" risk which was less than 1%.

In respect of what A considered to be material, the Court determined that A had accepted some risk, namely a risk of Down's syndrome as her first trimester test recorded a risk of 1:1753. On this basis, given that the risk of alternative chromosome abnormality was less than that of having a child with Down's syndrome, the Court did not accept that the theoretical risk of such abnormality needed to be conveyed to A, as she would not have considered it relevant.

2. Would A have undergone amniocentesis in the second trimester?

The evidence suggested that the risk of premature labour with a second trimester amniocentesis was 1%. Premature delivery increased the risk of the child being born with disabilities. In addition, of that 1%, there was a 10% chance of death. A argued that she would have accepted that risk given that she absolutely did not want a disabled child.

The Judge found that the risk of chromosomal abnormality was "theoretical". When compared to a real risk of premature delivery causing disability and/or death, the Court found that A would not have proceeded with amniocentesis when it was the evidence of the clinicians and the experts that the likely cause of restricted growth was placental dysfunction.

3. Would A have proceeded to termination of pregnancy at 32 or 35 weeks gestation?

A stated that whilst she understood the mechanism of late termination of pregnancy, she would have proceeded with the same had she known that the fetus had an unbalanced translocation which would cause significant disabilities.

The Court determined that A would not have proceeded to termination of pregnancy on the basis that when she was advised of possible premature delivery she was "shocked" and was willing to do what she could to maintain the pregnancy, even if that meant that she might have to deliver at any time and suffer the possible consequence of a having a disabled child.

Material risk and the need to obtain informed consent

The judgment in A is confirmation that the Court's decision in Montgomery does not mean a patient has to be informed of all risks. Material has to be more than "theoretical", "background" or "negligible". How the patient has communicated with her clinicians and the decisions taken during treatment are also relevant. A patient cannot simply rely on Montgomery to state they have an absolute right to know of all risks. The judgment in A is not only useful in identifying what material risk might mean, it also assists in outlining what a reasonable patient might want to know. The latter is based on their actions and discussions and a patient will not be able to rely on Montgomery where actions suggest that the risk would not have in fact been material to them.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.