We have used pulsed laser deposition to grow BiFeO3/BaTiO3 multilayers on SrTiO3 substrates. The samples are characterized by Reflection High Energy Electron Diffraction (RHEED), Atomic Force Microscopy (AFM), and by X-ray diffraction measurements and modelling. The two multilayers investigated here have modulation periods A = 90Å and 180Å, while the total thickness of 1800Å is the same for both samples. Hence, twice as many interfaces are encountered for the A = 90Å than for the A = 180Å sample. SQUID magnetometer measurements performed on these multiferroic samples show that the magnetization is significantly larger for the smaller wavelength sample thus pointing to a multilayer effect between the magnetic susceptibility and the number of interfaces per unit volume.