title: Vitrification of oocytes produces high pregnancy rates when carried out in fertile women.
abstract: OBJECTIVE
  To determine the efficiency of our vitrification technique when applied in young fertile women.
  
  
  METHODS
  Clinical research and application.
  
  
  METHODS
  In vitro fertilization center.
  
  
  METHODS
  Twenty-one women were recruited from the navy community with 19 patients finishing the study.
  
  
  METHODS
  Vitrified oocytes with use of the electron microscopic grid method were warmed 6 months after vitrification. Surviving metaphase II oocytes were microinjected for fertilization, and clinical results were evaluated.
  
  
  METHODS
  Survival, fertilization, and cleavage rate. Pregnancy and implantation rate.
  
  
  RESULTS
  Three hundred ninety-five oocytes were warmed, of which 320 oocytes (81.0%) survived. Two hundred eighty-five metaphase II oocytes were microinjected for fertilization; 206 of them (72.3%) fertilized, and 53 embryos were transferred to 19 patients (in 20 warming cycles). Twenty-four of 53 transferred embryos (45.3%) implanted as confirmed by ultrasound examination. Of the 20 transfers, 16 resulted in clinical pregnancy (80%), 3 miscarried (15%), and 13 (65%) went on to produce 20 live births, respectively. This is much higher in comparison with our previous data using supernumerary oocytes where the rates of implantation and pregnancy were 6% and 21%. Live-birth rates per warmed oocyte and per injected oocyte were 5.1% and 7.2%, respectively.
  
  
  CONCLUSIONS
  High pregnancy and implantation rates were observed after 6 months of cryopreservation by vitrification when oocytes from fertile woman were used. Proper screening of candidates for oocyte cryopreservation is of crucial importance to assure a favorable pregnancy outcome.
authors.affiliation: Reproductive Medicine Associates of New Jersey, Morristown, New Jersey, USA.
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Kim
authors.forename: Larry R
authors.initials: LR
authors.lastname: Laufer
authors.forename: Seung Wook
authors.initials: SW
authors.lastname: Hong
mesh_terms: D002470:Cell Survival; D010064:Embryo Implantation / Q000502:physiology; D004624:Embryo Transfer / Q000379:methods; D005260:Female; D005298:Fertility / Q000502:physiology*; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D008297:Male; D008677:Metaphase; D054315:Oocyte Retrieval / Q000379:methods*; D009865:Oocytes / Q000166:cytology / Q000502:physiology / Q000648:ultrastructure; D011247:Pregnancy; D018873:Pregnancy Rate; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods*; D013084:Sperm-Ovum Interactions / Q000502:physiology; D013094:Spermatozoa / Q000502:physiology; D015044:Zona Pellucida / Q000502:physiology