title: [Comparison of 3 techniques for artificial shrinkage of blastocoelic cavity before vitrification of expanded mouse blastocysts].
abstract: OBJECTIVE
  To establish an effective pretreatment method for the vitrification of expanded mouse blastocysts by comparing 3 techniques for the artificial shrinkage of the blastocoelic cavity.
  
  
  METHODS
  The blastocoelic cavity was artificially shrunk by micro-needle aspiration, pipetting or laser drilling prior to the vitrification of the expanded blastocysts. The rates of survival and hatching achieved with the three techniques were compared with those of the non-shrinkage group.
  
  
  RESULTS
  The rates of survival were 72.9, 72.0 and 94.0%, and those of hatching were 64.6, 32.0 and 62.0% in the three shrinkage groups, obviously higher than in the nonshrinkage group (40.0 and 16.0%).
  
  
  CONCLUSIONS
  Artificial shrinkage of the blastocoelic cavity was an effective pretreatment technique for the vitrification of expanded mouse blastocysts, especially by micro-needle aspiration and laser drilling.
authors.affiliation: Reproductive Medicine Center, Drum Tower Hospital Affiliated to Nanjing University School of Medicine, Nanjing, Jiangsu 210008, China.
authors.forename: Ning-yuan
authors.initials: NY
authors.lastname: Zhang
authors.forename: Hai-xiang
authors.initials: HX
authors.lastname: Sun
authors.forename: Ya-li
authors.initials: YL
authors.lastname: Hu
authors.forename: Zhi-peng
authors.initials: ZP
authors.lastname: Xu
authors.forename: Lin-jun
authors.initials: LJ
authors.lastname: Chen
authors.forename: Xia
authors.initials: X
authors.lastname: Zhao
mesh_terms: D000818:Animals; D001755:Blastocyst; D015925:Cryopreservation / Q000379:methods*; D046149:Embryo Culture Techniques / Q000379:methods*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR