"A mountaineer about to undertake a difficult climb is concerned about the fitness of his knee. He goes to a doctor who negligently makes a superficial examination and pronounces the knee fit. The climber goes on the expedition, which he would not have undertaken if the doctor had told him the true state of his knee. He suffers an injury which is an entirely foreseeable consequence of mountaineering but has nothing to do with his knee."
Lord Hoffman in South Australia Asset Management Corporation v York Montague  AC 191.
The GP is not liable if the mountaineer is injured in an avalanche. There was a duty of care. There was a breach of the duty of care. But for that breach the mountaineer would not have suffered injury in the avalanche. But the GP's duty of care did not extend to protecting the mountaineer from the dangers of avalanches.
"It is never sufficient to ask simply whether A owes B a duty of care. It is always necessary to determine the scope of the duty by reference to the kind of damage from which A must take care to save B harmless."
Lord Bridge in Caparao Industries Plc. V Dickman  2 AC 605 at 627.
In Meadows v Khan  EWHC 2990 (QB) the newly appointed Mrs Justice Yip, was faced with the defendant's argument that the SAAMCO principle applied to defeat (part of) a wrongful birth claim.
The claimant mother's nephew had haemophilia. The claimant sought advice from the defendant on whether she was a carrier. She was tested for having haemophilia, the tests were negative, but negligently she was not advised that this did not rule out that she could be carrier. She went on to become pregnant and to give birth to her son who did have (severe) haemophilia. He also had autism.
The defendant contended that whilst it was liable to compensate the claimant for the costs of raising a child with haemophilia, the defendant had not been consulted about anything other than the chance of the claimant being a carrier of haemophilia. Hence, losses and expenses to the mother associated with her son's autism were not the kind of damage that the defendant had a duty of care to prevent.
Mrs Justice Yip rejected this argument. She reviewed case law including Parkinson v St James and Seacroft University Hospital NHS Trust  QB 266 and Groom v Selby  PIQR P18. She held:
"...the effect of the doctor's negligence was to remove the mother's opportunity to terminate a pregnancy that she would not have wanted to continue. To draw a distinction on the basis of considering the underlying reason why a mother would have wanted to terminate her pregnancy seems unattractive, arbitrary and unfair."
The pregnancy and birth were not "divisible". The purpose of the consultation was to allow the claimant to make an informed decision about whether to have a child. The conception and birth arose from the negligent advice. Once the child is born and has a disability then there can be no separation of the effect of different disabilities or conditions. The Courts in Parkinson and Groom allowed for recovery for damages related to the child's disability where the birth of the child but not its disability, was directly related to the defendant's negligence. So it should be in the present case. The defendant was liable to the claimant mother in respect of the child's autism as well as his haemophilia.
If the child had suffered injury due to non-negligently caused hypoxia during the late state of labour and delivery, then presumably the same principle would apply. However, wrongful birth cases have always concerned a condition that is inherited rather than one that is a product of environment or circumstances. What if a child would not have been born but for the negligence of the defendant, but is born healthy only to suffer from brain damage due to hypoxia as a neonate? The child is disabled all its life. But would the mother have a claim?