You could use a macro like:
Code:
Sub Demo()
Application.ScreenUpdating = False
Dim Sctn As Section, iShp As InlineShape, Shp As Shape, sWdth As Single, sHght As Single
For Each Sctn In ActiveDocument.Sections
With Sctn
With .PageSetup
sWdth = .PageWidth - .LeftMargin - .RightMargin - .Gutter
sHght = .PageHeight - .TopMargin - .BottomMargin
End With
For Each iShp In .Range.InlineShapes
With iShp
.LockAspectRatio = True
If .Width > sWdth Then .Width = sWdth
If .Height > sHght Then .Height = sHght
End With
Next
For Each Shp In .Range.ShapeRange
With Shp
.LockAspectRatio = True
If .Width > sWdth Then .Width = sWdth
If .Height > sHght Then .Height = sHght
End With
Next
End With
Next
Application.ScreenUpdating = True
End Sub