title: Aseptic vitrification of human germinal vesicle oocytes using dimethyl sulfoxide as a cryoprotectant.
abstract: OBJECTIVE
  To evaluate the viability of vitrified human germinal vesicle (GV)-oocytes to mature to metaphase II (MII) stage after "rapid" cooling directly in liquid nitrogen in comparison with "slow" cooling in a closed 0.5-mL straw (aseptic system), with or without dimethyl sulfoxide (DMSO) in vitrification solution. The possibility of avoiding parthenogenesis of the oocytes after vitrification using DMSO was investigated.
  
  
  METHODS
  In vitro maturation after vitrification.
  
  
  METHODS
  Assisted reproduction centers.
  
  
  METHODS
  Patients undergoing standard superovulation treatment and having GV-oocytes after follicular puncture.
  
  
  METHODS
  The GV-oocytes were vitrified with long/short exposure to DMSO using slow or rapid cooling, then warmed and matured in vitro.
  
  
  METHODS
  Maturation after warming.
  
  
  RESULTS
  Oocyte development up to MII stage after vitrification with DMSO was 71% in the group with "rapid" cooling, and in groups with "slow" cooling, 68% and 72% for long and short exposure to DMSO, respectively. The maturation rate of GV-oocytes after slow cooling without DMSO was 51%. In the vitrification with long-term contact of oocytes with DMSO group, a high rate of parthenogenesis was observed. When vitrification with short-term contact of oocytes with DMSO at room temperature was used, no parthenogenesis was observed.
  
  
  CONCLUSIONS
  Cryopreservation of human GV-oocytes in open-pulled straws OPS) using an aseptic slow cooling method gives high maturation rates but only in combination with DMSO. To avoid spontaneous parthenogenesis, the exposure to DMSO must occur for a reduced time and at room temperature.
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: Salvatore
authors.initials: S
authors.lastname: Dessole
authors.forename: Frank
authors.initials: F
authors.lastname: Nawroth
authors.forename: Hans
authors.initials: H
authors.lastname: van der Ven
mesh_terms: D001207:Asepsis; D002470:Cell Survival / Q000187:drug effects; D016922:Cellular Senescence / Q000187:drug effects; D015925:Cryopreservation / Q000379:methods*; D003451:Cryoprotective Agents / Q000008:administration & dosage / Q000494:pharmacology*; D004121:Dimethyl Sulfoxide / Q000008:administration & dosage / Q000494:pharmacology*; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008677:Metaphase; D009865:Oocytes / Q000166:cytology / Q000187:drug effects* / Q000502:physiology; D010312:Parthenogenesis / Q000187:drug effects; D013997:Time Factors
chemical_list: D003451:Cryoprotective Agents; D004121:Dimethyl Sulfoxide