  In this paper we review some properties for the evolving wormhole solution of
Einstein equations coupled with nonlinear electrodynamics. We integrate the
geodesic equations in the effective geometry obeyed by photons; we check out
the weak field limit and find the traversability conditions. Then we analyze
the case when the lagrangian depends on two electromagnetic invariants and it
turns out that there is not a more general solution within the assumed
geometry.
