More accurately, she wasn't even a sparkle in DC Comics's eye; she was first seen (as a grown adult) in 1977 and then retconned into previous existence. (So she would have been born by then.)
And Earth-2's marriage of Bruce and Selina was also retconned in with that story.
It came up again later in stories like The Brave and the Bold #197 (cover-dated April 1983) and the Mr. & Mrs. Superman feature story in Superman Family #211 (cover-dated October 1981).