Abstract: 
The Coupling of matter fields to spin foam models of quantum gravity will be
discussed. We will show in the case of three dimensional gravity how the
integration of quantum gravity degrees of freedom coupled to matter can be
explicitely described in terms of an effective field theory.
This theory is a new non commutative field theory obeying the principle of
doubly special relativity. We will conclude on the extension of this
approach to the four dimensional case.
