An independent review has been ordered into the incorrect programming of cochlear ear implants for as many as 30 children in South Australia which left them unable to hear all the sounds necessary for learning and speech.

Health Minister Chris Picton said on Monday an interstate expert would be brought in to find out what went wrong for the past four or more years and to ensure the situation was not repeated.

The minister said families of the children would also be involved in the review with some patients still being followed up.

"There's clearly some series issues that have been uncovered in terms of that mapping work which should have been done properly at the beginning," Mr Picton said.

The children involved were under the care of South Australia's Women's and Children's Health Network which became aware of problems with some implants last year.

A check of all 117 families in the program identified issues in about 30 children who had lived with incorrectly programmed implants for periods of up to five years.

Testing showed their implants were programmed in a way that they could not hear speech sounds at a level that would allow them to learn to listen and speak.

Mr Picton said "everything will be on the table" in the review to find out what happened.

"When issues arise, we have to work out what's happened and we have to work out how we can prevent that from happening in the future," he said.

"Certainly, if there were systemic management issues as part of this, that led to this problem over many years, then that will absolutely be a subject that this external review will be able to look at."

Opposition Leader David Speirs said it was heartbreaking to learn the children involved had likely suffered irreversible harm to their communication skills.

"It's crucial children who are born deaf or hard of hearing have early and appropriate intervention, as untreated hearing loss can have profound effects on a child's ability to develop speech, language and social skills," he said.