Preimplantation Genetic Diagnosis (PGD) has been proposed as a potential means to achieve these goals, but so far, the results with day 3 biopsy and FISH analysis of 5-12 chromosomes has produced contradictory results, the difference between studies being explained by technical differences (Munne et al. 2010). Three technical developments have recently occurred that can change dramatically the efficacy of PGD. One, blastocyst laser assisted biopsy, which seems less detrimental than cleavage stage biopsy; Two, vitrification of embryos which allows those blastocysts to be frozen with little or no loss of viability, and three, chromosome comprehensive screening techniques, such as array CGH (Gutierrez-Mateo et al. 2011) which allow for the detection of all chromosome abnormalities.