title: Influence of embryo transfer on embryo preimplantation development.
abstract: OBJECTIVE
  To investigate the impact of injection speeds of the transferred load on embryo development.
  
  
  METHODS
  A laboratory model for in vitro simulation of ET was developed to investigate the impact of varying injection speeds of the transferred load on embryo development.
  
  
  METHODS
  Academic research institutes of reproduction biotechnology and private centers of reproductive medicine.
  
  
  METHODS
  Mouse hybrid F(1) females (C57bl/10 J × CBA-H; N = 15) aged 2-3 months.
  
  
  METHODS
  In vitro exposure of mouse embryos with either the fast ET (ejection speed, >1 m/s) or slow ET (ejection speed, <0.1 m/s) and consecutive culture for 36 hours.
  
  
  METHODS
  Development rate, morphology and apoptotic index of embryos.
  
  
  RESULTS
  The development rate was the slowest in embryos exposed to the fast ET. Morphological changes in response to ET were observed only among embryos exposed to the fast ET. The mean apoptotic index was 17.6% in the group exposed to the fast ET, 5.6% in the group exposed to the slow ET, and 2.58% in the control group.
  
  
  CONCLUSIONS
  A reduction of the ejection speed of the transferred load allows avoidance of a developmental delay and diminishes injury of the embryos. Therefore, it is reasonable to suggest transferring the embryos at the lowest possible ejection 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: Pietrewicz
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: Bartosz
authors.initials: B
authors.lastname: Pietrzycki
authors.forename: Grzegorz
authors.initials: G
authors.lastname: Mrugacz
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D001755:Blastocyst / Q000166:cytology* / Q000502:physiology*; D002452:Cell Count; D053938:DNA Fragmentation; D004624:Embryo Transfer / Q000379:methods*; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D007267:Injections / Q000009:adverse effects / Q000379:methods; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D009028:Morula / Q000166:cytology / Q000502:physiology; D011247:Pregnancy; D011312:Pressure / Q000009:adverse effects; D013997:Time Factors