Promponas, E. Keramitsoglou, T. Pantos, K. Vaxevanoglou, T. and Spyropoulou-Vlachou, M. Koussoulakos, S. Varla-Leftherioti, M. Barnea, E. R., Embryo selection based on preimplantation factor (PIF) positivity and good morphology improve IVF success, Journal of Reproductive Immunology, (86), 41, 2010, Elsevier Ireland Ltd, 0165-0378