  We analyze the validity of the theorems concerning the cancellation of the
infrared and collinar divergences in the case of dark matter freeze-out in the
early universe. In particular, we compute the electroweak logarithmic
corrections of infrared origin to the annihilation cross section of a dark
matter particle being the neutral component of a SU(2)_L multiplet. The
inclusion of processes with final state W can modify significantly the cross
sections computed with only virtual W exchange. Our results show that the
inclusion of infrared logs is necessary for a precise computation of the dark
matter relic abundance.
