title: Influence of embryo transfer on blastocyst viability.
abstract: OBJECTIVE
  To investigate the impact of injection speeds of the transferred load on embryo viability.
  
  
  METHODS
  Laboratory model for in vitro simulation of embryo transfer (ET).
  
  
  METHODS
  Academic research institutes of reproduction biotechnology and private centers of reproductive medicine.
  
  
  METHODS
  Mouse hybrid F1 females, C57bl/10J × CBA-H (N = 15), aged 2 to 3 months.
  
  
  METHODS
  In vitro exposure of mouse blastocysts to either fast ET with an ejection speed of the transferred load of >1 m/s or slow ET with an ejection speed of <0.1 m/s.
  
  
  METHODS
  Morphologic changes and apoptotic index of blastocysts.
  
  
  RESULTS
  Morphologic changes in response to ET were most prevalent in blastocysts exposed to fast ET. The mean apoptotic index was 52% in the group exposed to fast ET, 25% in the group exposed to slow ET, and 12.8% in control group.
  
  
  CONCLUSIONS
  Fast ejection of the transferred load can trigger both morphologic changes and apoptosis in mouse blastocysts. A reduction of the ejection speed of the transferred load minimizes injury to the embryos. Therefore, embryos should be transferred at the lowest possible speed.
authors.affiliation: Center for Reproductive Medicine BOCIAN, Bialystok, Poland. cezary.grygoruk@gmail.com
authors.forename: Cezary
authors.initials: C
authors.lastname: Grygoruk
authors.forename: Piotr
authors.initials: P
authors.lastname: Sieczynski
authors.forename: Jacek A
authors.initials: JA
authors.lastname: Modlinski
authors.forename: Barbara
authors.initials: B
authors.lastname: Gajda
authors.forename: Pawel
authors.initials: P
authors.lastname: Greda
authors.forename: Izabela
authors.initials: I
authors.lastname: Grad
authors.forename: Piotr
authors.initials: P
authors.lastname: Pietrewicz
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Mrugacz
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology; D001755:Blastocyst / Q000166:cytology* / Q000502:physiology*; D002470:Cell Survival / Q000502:physiology; D004624:Embryo Transfer / Q000379:methods*; D005260:Female; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011247:Pregnancy