title: The quality of human embryo growth is improved when embryos are cultured in groups rather than separately.
abstract: OBJECTIVE
  To determine the effect of culturing human embryos in groups on cleavage rates, morphology grades, and embryo scores when compared with embryos cultured singly.
  
  
  METHODS
  Prospective.
  
  
  METHODS
  The IVF-ET program of the Pennsylvania State University, Department of Obstetrics and Gynecology, Hershey Medical Center, Hershey, Pennsylvania.
  
  
  METHODS
  Fifty-five infertile women who each had at least five zygotes underwent IVF-ET.
  
  
  METHODS
  Zygotes from each patient were allocated to be cultured singly and in groups.
  
  
  METHODS
  Cleavage rate, morphology grade, and embryo score.
  
  
  RESULTS
  Grouping embryos significantly enhanced cleavage rates and embryo scores but not morphology grade as compared with embryos grown singly. Additionally, the size of the groups correlated positively with cell number and embryo score but not the morphology grade.
  
  
  CONCLUSIONS
  Culturing human embryos in groups enhances the quality of their growth by increasing the cleavage rates and embryo scores. Because pregnancy rates are improved by transferring embryos with higher embryo scores, coculturing human embryos may be a way of enhancing pregnancy rates.
authors.affiliation: Pennsylvania State University, Department of Obstetrics and Gynecology, College of Medicine, Hershey Medical Center, Hershey 17033, USA.
authors.forename: J
authors.initials: J
authors.lastname: Moessner
authors.forename: W C
authors.initials: WC
authors.lastname: Dodson
mesh_terms: D002455:Cell Division / Q000502:physiology; D002478:Cells, Cultured; D018920:Coculture Techniques / Q000379:methods / Q000592:standards*; D046508:Culture Techniques; D004624:Embryo Transfer; D004622:Embryo, Mammalian / Q000166:cytology* / Q000502:physiology; D005314:Embryonic and Fetal Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D018873:Pregnancy Rate; D011446:Prospective Studies