Sub CheckSecLen() 
    Dim iSec As Integer 
    Dim oRng As Range 
    Dim iValue As Integer 
    With ActiveDocument 
         ' go through each section (except for the last one)
        For iSec = 1 To .Sections.Count - 1 
             ' create a range object at the start of the section
            Set oRng = .Sections(iSec).Range 
            oRng.Collapse wdCollapseStart 
             ' insert a sectionpages field
            .Fields.Add Range:=oRng, Type:=wdFieldSectionPages 
             ' divide the sectionpages field by 2
             ' if it gives a zero as the remainder, then
             ' you have an even number of pages in the section,
             ' which is what you want with an odd section page break
            If (.Sections(iSec).Range.Fields(1).Result Mod 2) <> 0 Then 
                 ' if you have an odd number of pages, then insert
                 ' a page break before the section's section break
                Set oRng = .Sections(iSec).Range 
                With oRng 
                    .Collapse Direction:=wdCollapseEnd 
                    .MoveEnd unit:=wdCharacter, Count:=-1 
                    .InsertBreak Type:=wdPageBreak 
                End With 
            End If 
             ' remove the sectionpages field that was added
            .Sections(iSec).Range.Fields(1).Delete 
        Next iSec 
    End With 
End Sub