The nurse went on to tell the radio personalities that the duchess had had an uneventful night, as a dog barking sound was heard in the background. The alleged queen and prince talk about traveling to the hospital to check in on the patient.
The hospital said it supported Saldanha in the aftermath of the call and that its phone protocols were under review.
The Australian station placed the recording of the conversation on its website, but later said it was sorry.
"We were very surprised that our call was put through. We thought we'd be hung up on as soon as they heard our terrible accents," Greig and Christian said in a joint statement with the station at the time. "We're very sorry if we've caused any issues and we're glad to hear that Kate is doing well."
Officials from St. James's Palace have said the duchess is not yet 12 weeks pregnant. The child would be the first for her and Prince William.
Associated Press writers Paisley Dodds in London and Kristen Gelineau in Sydney contributed to this story.
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