An Etymological Dictionary of the German Language/schwanger

by Friedrich Kluge

schwanger, adj., ‘pregnant, teeming,’ from the equiv. MidHG. swanger, OHG. swangar; comp. Du. zwanger, ‘pregnant,’ but AS. swǫngor, ‘awkward, idle’; the latter meaning makes the derivation from schwingen improbable. AS. has also the curious form swǫncor; see schwank.