  We discuss the relevance of quantum gravitational corrections to the
functional Schr\"odinger equation for the information loss paradox in black
hole evaporation. These corrections are found from the Wheeler-DeWitt equation
through a semiclassical expansion scheme. The dominant contribution in the
final evaporation stage, when the black hole approaches the Planck regime, is a
term which explicitly violates unitarity in the non-gravitational sector. While
pure states remain pure, there is an increase in the degree of purity for
non-pure states in this sector. This result holds irrespective of whether full
quantum gravity respects unitarity or not.
