Australian Medical Association (WA) president Omar Khorshid says it's unacceptable the state's biggest maternity hospital doesn't have an ICU or CT scanner.

Doctors are concerned Western Australia's biggest maternity hospital still doesn't have an intensive care unit, meaning seriously ill women are "tossed into an ambulance" and sent to the nearest emergency department.

The 101-year-old, heritage-listed King Edward Memorial Hospital caters for complex pregnancies and high-risk births but also does not have a CT scanner.

"Women who are very sick - either obstetrics or a gynaecological cancer and so on - have no access to an intensive care unit," Australian Medical Association (WA) president Omar Khorshid told AAP.

"How is that acceptable in the modern age? It's archaic."

Dr Khorshid said he hoped KEMH would be the next major hospital project but didn't expect it any time soon given there had been big investments in Perth hospitals in recent years and state finances were dire.

He also commented on the long-delayed and trouble-plagued Perth Children's Hospital, which shows no sign of opening soon as work continues to remove lead contamination from the drinking water.

While potable water had to be completely safe, he said the AMA would accept lower standards for water that was not consumed and used in air conditioning or sterilising machines, for example, if it meant opening the hospital earlier.

"If they have to make practical decisions around the lead that means the hospital will not be delayed for another year, then we would support them," Dr Khorshid said.

"Not every part of the hospital that uses water has any contact with the patients or staff or visitors."

He also said the opening delay should be used to thoroughly determine the safety of all building materials such as external cladding in light of the Grenfell Tower disaster.

"We understand it's OK, but we're not certain," he said.

"It might have the right certification and the right paperwork came with it, but has anyone drilled into it to see what's actually in there?

"I'm sure the roof panels said they didn't have asbestos in them."