Gravitino production during preheating and the equivalence theorem

We review our results on the calculation of helicity 1/2 gravitino production during preheating. The method we present is based on the equivalence between goldstinos and longitudinal gravitinos at high energies. The problem is thus reduced to the standard (Majorana) fermion production after inflation. Comparison between helicity 3/2 and 1/2 production and with the results obtained in the unitary gauge is also presented.