The impact of pronuclear orientation to select chromosomally normal embryos

Purpose: To find an effective method to select embryos from ICSI with better chromosomal status when preimplantation-genetic-diagnosis (PGD) is not applied.Methods: Several morpholological evaluations were done in same embryos. Embryos from ICSI were classified on day I according to pronuclear-nucleoli arrangement. On day 3, classification was done according to number, fragmentation, size and shape of cells. in some patients, embryos exhibiting good quality on day 3 (at least six regular blastomeres with cell fragmentation lower than 20%) were also submitted to PGD, irrespective to pronuclear-nucleoli morphology.Results: Forty-two per cent of normally fertilized embryos showed pronuclear-nucleoli-good-morphology; from those, 86% were also classified as good quality on day 3. Good-quality embryos submitted to PGD have shown lower chromosomal abnormality rates when also classified as pronuclear-nucleoli-good-morphology.Conclusions: Pronuclear-nucleoli morphology seems to be correlated with PGD results. This criterion may prove useful for pre-select embryos with normal chromosomal package when PGD is not applied.Fertil Ctr Fertilizacao Assistida, BR-01402002 São Paulo, BrazilMed Sch Jundiai, Fertil Ctr, Jundiai, SP, BrazilGenet Lab, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilUniversidade Federal de São Paulo, São Paulo, BrazilWeb of Scienc