  Waveforms of gravitational waves provide information about a variety of
parameters for the binary system merging. However, standard calculations have
been performed assuming a FLRW universe with no perturbations. In reality this
assumption should be dropped: we show that the inclusion of cosmological
perturbations translates into corrections to the estimate of astrophysical
parameters derived for the merging binary systems. We compute corrections to
the estimate of the luminosity distance due to velocity, volume, lensing and
gravitational potential effects. Our results show that the amplitude of the
corrections will be negligible for current instruments, mildly important for
experiments like the planned DECIGO, and very important for future ones such as
the Big Bang Observer.
