title: Is pronuclear scoring a really good predictor for ICSI cycles?
abstract: OBJECTIVE
  Since the assessments of the morphology of oocytes, zygotes and/or embryos are of crucial importance to select the best candidate for pregnancy, many morphological evaluation tools have been proposed. Although embryo scoring, particularly cleavage and blastocyst stages, is more convincing due to successful results, zygote scoring still have a bias as different outcomes. In the current study, we designed a prospective study to test the reliability of zygote scoring by focusing on zygote evaluation techniques and its relation with embryo development and embryo selection for transfer.
  
  
  METHODS
  A total of 1215 mature oocytes from 139 couples were evaluated for the study.
  
  
  RESULTS
  There is no correlation between published zygote scoring technique and embryo development.
  
  
  CONCLUSIONS
  We conclude that the inconsistency of data obtained from zygote scoring might be caused by the static nature of pronuclear stage embryos and thus pronuclear scoring seems to be unreliable evaluation technique for embryo selection.
authors.affiliation: Center for Assisted Reproductive Medicine and IVF, Etlik Zubeyde Hanim Women's Health Teaching and Research Hospital, Ankara 06010, Turkey. aydinsevim@yahoo.com
authors.forename: Sevim
authors.initials: S
authors.lastname: Aydin
authors.forename: Ozgur
authors.initials: O
authors.lastname: Cinar
authors.forename: Berfu
authors.initials: B
authors.lastname: Demir
authors.forename: Cem
authors.initials: C
authors.lastname: Korkmaz
authors.forename: Ozlem
authors.initials: O
authors.lastname: Ozdegirmenci
authors.forename: Serdar
authors.initials: S
authors.lastname: Dilbaz
authors.forename: Umit
authors.initials: U
authors.lastname: Goktolga
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000502:physiology / Q000648:ultrastructure; D002467:Cell Nucleus / Q000648:ultrastructure*; D004477:Ectogenesis; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000503:physiopathology* / Q000628:therapy*; D008297:Male; D011446:Prospective Studies; D015203:Reproducibility of Results; D020554:Sperm Injections, Intracytoplasmic; D015053:Zygote / Q000502:physiology* / Q000648:ultrastructure*