  The possible amplification of gauge invariant metric fluctuations in the
infrared sector are very important during reheating stage of inflation. In this
stage the inflaton oscillates arount the minimum of the scalar potential. The
evolution for super Hubble scales gauge invariant metric fluctuations can be
studied by means of the Bardeen parameter. For a massive scalar field with a
quadratic potential for a nonzero cosmological constant. I find that (in the
reheating regime and for super Hubble scales), the Sasaki-Mukhanov parameter
oscillates with amplitude constant such that there is no amplification of $Q$
during reheating.
