"Four weeks ago, Warner’s partner, the singer Claire Egan, gave birth to a baby girl"
I thought it was pretty clear.
The article does initially say that 'Warner has been busy bringing a new life into the world' which for me would imply that she did so physically so I can understand the confusion.
It's no different to a man father a child in his sixties which isn't that unusual.
Personally I don't think its a great idea either way.