The Perth hospital in which a woman gave birth to a stillborn baby without staff noticing has defended its level of care.

Sharon May was in an induced coma in intensive care while being treated for pneumonia and swine flu at Sir Charles Gairdner Hospital.

Mrs May was 24 weeks' pregnant, when last month while still in a coma she gave birth to a stillborn boy.

He was found in her bed when a nurse checked on her.

Mrs May's husband, Danny, says the system has let the family down.

"I think they failed us big time," he said.

"How can you grieve? The body is a broken vessel at the moment.

"How do you deal with it? It's not a question I can answer."

Hospital management says it is doing all it can to assist the family and it stands by its medical care delivered to all patients admitted with swine flu.

Spokeswoman Dr Shirley Bowen says the level of care was appropriate.

"We do not believe we have provided anything but excellent care to this woman," she said.

"We provided a high standard of care. We followed the obstetrician's advice completely.

"I do not believe that there was anything in terms of her care that should have been provided and did not provide to prevent this outcome."

The May family's lawyer has called for a coronial investigation.

Mr May's lawyer, John Hammond, says there needs to be a coronial inquiry.

"And there should be a full ministerial investigation as to why the health system has so dramatically failed and is it now in a permanent state of collapse," he said.