She said her evidence to the court that she would have chosen to abort the pregnancy if she and her partner had been told of their daughter's condition at 20 weeks' pregnancy was difficult testimony to give.
"Obviously once she's with us we want and love her," the mother said yesterday. "But it's like trying to think back, 'How would we have reacted?' and we had to just discuss and kind of make that choice after the fact, which was very difficult."
The woman was told by sonographer Paul Kendrick and radiologist Dr Richard Gee, of Horizon Scanning, at her 20-week scan that "no anatomical abnormality" was detected.
Days after the birth, Dr Bruce Allen, chief radiologist at Horizon Scanning, sent the mother a written apology "for their failure to diagnose the spina bifida from that 20-week scan".
"Subsequent independent specialist opinion would indicate that the signs were there to be seen in that scan but were simply overlooked," court documents say.
The mother applied to ACC for cover for injury as a result of her continued pregnancy based on the incorrect advice.
"[She] says she would have sought termination of pregnancy if disclosure had been made to her at the time of the scan," court documents say.
However, ACC declined cover, saying her claim did not meet the criteria for "treatment injury".
The mother has had her appeals to the District Court and High Court dismissed. But her bid to the Court of Appeal has been successful and is expected to be heard later this year.
The woman's lawyer, Philip Schmidt, said it was "likely that the Court of Appeal's decision will have a significant influence on what claims for pregnancy-related injury will be covered by ACC in the future".
An ACC spokeswoman said it would be inappropriate to comment while court proceedings were under way.
Horizon Scanning chief executive Mary Gordon said she could not comment for privacy reasons.