Assuming they're active hyperlinks and the document contains no other hyperlinks, you could use a macro like:
Code:
Sub Demo()
Application.ScreenUpdating = False
Dim i As Long, Rng As Range, StrAddr As String
With ActiveDocument
For i = .Hyperlinks.Count To 1 Step -1
Set Rng = .Hyperlinks(i).Range
StrAddr = Chr(34) & .Hyperlinks(i).Address & Chr(34)
.Fields.Add Rng, Type:=wdFieldIncludePicture, Text:=StrAddr, PreserveFormatting:=False
Next
End With
Application.ScreenUpdating = True
End Sub
For macro installation & usage instructions, see:
http://www.gmayor.com/installing_macro.htm