Sub FieldsUpdated()
  Dim aFld As Field, sBefore As String, sAfter As String
  Dim sMsg As String, iChangeCount As Integer
  For Each aFld In ActiveDocument.Fields
    sBefore = aFld.Result
    aFld.Update
    sAfter = aFld.Result
    If sBefore <> sAfter Then
      aFld.Result.HighlightColorIndex = wdDarkYellow
      iChangeCount = iChangeCount + 1
    End If
  Next aFld
  If iChangeCount > 0 Then
    MsgBox iChangeCount & " field(s) were changed. Look for the dark yellow highlights"
  Else
    MsgBox "No field changes"
  End If
End Sub