expression.Saved
expression Required. An expression that returns one of the objects in the Applies To list.
Remarks
If the Saved property of a modified publication returns True, the user won't be prompted to save changes when closing the publication, and all changes made to it since it was last saved will be lost.
Example
This example saves the active publication if it's been changed since the last time it was saved.
Sub Saver()
With Application.ActiveDocument
If Not .Saved And .Path <> "" Then .Save
End With
End Sub