We study the kinetics of domain growth of fluid mixtures quenched from a disordered to a lamellar phase. At low viscosities, in two dimensions, when hydrodynamic modes become important, dynamical scaling is verified in the form C(k,t) ∼ L^αf[(k − k_M)L], where C is the structure factor with maximum at k_M and L is a typical length with logarithmic growth at late times. The presence of extended defects can explain the behavior of L. Three-dimensional simulations confirm that diffuse grain boundaries inhibit complete ordering of lamellae. Applied shear flow alleviates frustration and gives power law growth at all times.