The Supreme Court makes it clear that when it comes to informed consent, patients have a right to know

In Montgomery v Lanarkshire Health Board, the Supreme Court has clarified the law in relation to informed consent.1 When seeking consent, doctors must take reasonable steps to ensure that the patient is aware of the material risks of any treatments they offer and of the availability of any reasonable alternatives. Doctors can no longer rely on a responsible body of medical opinion—the Bolam test—when assessing what information they should provide to patients.

The patient in the case was an insulin dependent diabetic pregnant woman. Diabetic women frequently have larger than normal babies, which leads to a heightened risk of shoulder dystocia where the baby's shoulders cannot pass through the pelvis. Her consultant did not inform her either of the 9%–10% risk of shoulder dystocia or of the possibility of delivery by caesarean section. During delivery the umbilical cord was occluded and her son was born with cerebral palsy and with a paralysis of the arm resulting from the vigorous manipulation required to deliver him.

The court held that the consultant should have informed the patient of the risks of shoulder dystocia and discussed the possibility of a caesarean section. The court also set out doctors’ legal obligations in relation to information provision when seeking consent. Doctors must ‘take reasonable care to ensure that the patient is aware of any material risks involved in any treatment and of any reasonable alternative or variant treatments’.2 A ‘material risk’ is one in which ‘a reasonable person in the patient’s position would be likely to attach significance to the risk, or the doctor is or should reasonably be aware that the particular patient would be likely to attach significance to it’.3 When discussing risk with patients, percentages alone are insufficient. Important factors will include ‘the nature of the risk, …