  The equilibrium phase diagram of a two-dimensional Ising model with competing
exchange and dipolar interactions is analyzed using a Monte Carlo simulation
technique. We consider the low temperature region of the (delta,T) phase
diagram (delta being the ratio between the strengths of the exchange and
dipolar interactions) for the range of values of delta where striped phases
with widths h=1 and h=2 are present. We show that the transition line between
both phases is a first order one. We also show that, associated with the first
order phase transition, there appear metastable states of the phase h=2 in the
region where the phase h=1 is the thermodynamically stable one and viceversa.
