title: Vitrification of mouse oocyte using open pulled straws compared with needles.
abstract: OBJECTIVE
  To compare the survival rate of mouse oocytes and fertilization rate between using open pulled straws (OPS) and needles for vitrification.
  
  
  METHODS
  Meiosis II oocytes from female C57B/6J mice aged 7-8 weeks were collected and allocated to two groups for vitrification by using OPS or needles. Vitrified oocytes were thawed, morphological survival and fertilization rate were examined.
  
  
  RESULTS
  There was no obvious difference between the morphological survival rates of vitrified mouse oocytes using OPS and needles (66.7% vs 64.8%). Proportions Difference 1.9% (95% CI -7.1, 10.7). The vitrified oocytes from the needle had significantly higher percentages of fertilization rate than OPS (76.8% vs 62.5%). Proportions Difference -14.3% (95% CI -24.5, -3.6).
  
  
  CONCLUSIONS
  Vitrification method of mouse oocytes using needles when compared to OPS provides a similar morphological survival rate and higher fertilization rate.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand.
authors.forename: Surachai
authors.initials: S
authors.lastname: Pornwiroon
authors.forename: Somboon
authors.initials: S
authors.lastname: Kunathikom
authors.forename: Orawan
authors.initials: O
authors.lastname: Makemaharn
authors.forename: Rattanaphorn
authors.initials: R
authors.lastname: Huanaraj
mesh_terms: D000818:Animals; D015925:Cryopreservation / Q000295:instrumentation* / Q000379:methods*; D005260:Female; D008540:Meiosis; D051379:Mice; D008810:Mice, Inbred C57BL; D009339:Needles; D009865:Oocytes / Q000648:ultrastructure*