title: Vitrification of mouse pronuclear embryos after polar body biopsy without direct contact with liquid nitrogen.
abstract: OBJECTIVE
  To evaluate the viability of vitrified mouse pronuclear embryos after polar body biopsy by cooling directly in liquid nitrogen in comparison with cooling in closed 0.5 mL straw (aseptic system).
  
  
  METHODS
  In vitro culture after vitrification.
  
  
  METHODS
  Department of Gynecological Endocrinology and Reproductive Medicine, University of Bonn, Germany.
  
  
  METHODS
  Superovulated mice.
  
  
  METHODS
  Biopsied embryos were vitrified, warmed, and cultured in vitro.
  
  
  METHODS
  Development after warming.
  
  
  RESULTS
  Development rates up to expanded blastocyst stage after in vitro culture were 25% in group with "direct" vitrification and 23% in group with "straw in straw" vitrification.
  
  
  CONCLUSIONS
  Cryopreservation of biopsied mouse pronuclear embryos in open-pulled straws, which are placed inside a hermetically closed container, guarantees a complete isolation of embryos from liquid nitrogen and avoids potential contamination by pathogenic microorganisms. The combination of plunging this container into liquid nitrogen and rapid warming makes this process as efficient as conventional vitrification.
authors.affiliation: Department of Gynecological Endocrinology and Reproductive Medicine, University of Bonn, Bonn, Germany. vovaisachenko@yahoo.com
authors.forename: Vladimir
authors.initials: V
authors.lastname: Isachenko
authors.forename: Markus
authors.initials: M
authors.lastname: Montag
authors.forename: Evgenia
authors.initials: E
authors.lastname: Isachenko
authors.forename: Hans
authors.initials: H
authors.lastname: van der Ven
mesh_terms: D000818:Animals; D001706:Biopsy; D015925:Cryopreservation / Q000379:methods*; D046149:Embryo Culture Techniques / Q000379:methods; D004622:Embryo, Mammalian / Q000166:cytology*; D005260:Female; D051379:Mice; D008809:Mice, Inbred C3H; D009865:Oocytes / Q000166:cytology*; D015053:Zygote / Q000166:cytology*