title: Live births after vitrification of oocytes in a stimulated in vitro fertilization-embryo transfer program.
abstract: OBJECTIVE
  To assess the usefulness of the vitrification method in clinical practice.
  
  
  METHODS
  Clinical study of vitrification of human oocytes.
  
  
  METHODS
  A university-affiliated hospital.
  
  
  METHODS
  Thirty-four patients who agreed to undergo additional IVF-ET after the failed fresh cycle using the previously vitrified/thawed oocytes.
  
  
  METHODS
  Surplus oocytes from the IVF-ET patients were vitrified for the next cycle.
  
  
  METHODS
  Morphologic normality of post-thawed oocytes, fertilization, cleavage, pregnancy, and implantation rate.
  
  
  RESULTS
  Overall morphological survival and fertilization rates of vitrified/liquefied oocytes were 68.6% (325/474) and 71.7% (142/198), respectively. Pregnancy rate and implantation rate per embryo transfer were 21.4% (6/28) and 6.4% (8/125), respectively. All pregnancies resulted in the delivery of healthy babies (1 twin and 5 singletons/6 pregnancies).
  
  
  CONCLUSIONS
  The feasibility of the vitrification method for human oocytes was confirmed by our clinical results. Subsequent studies on vitrification and thawing procedures should be undertaken for further optimizing the vitrification method.
authors.affiliation: College of Medicine, Pochon CHA University and Infertility Medical Center of CHA General Hospital, Seoul, South Korea. tkyoon@cha.ac.kr
authors.forename: Tae Ki
authors.initials: TK
authors.lastname: Yoon
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Kim
authors.forename: Sung Eun
authors.initials: SE
authors.lastname: Park
authors.forename: Seung Wook
authors.initials: SW
authors.lastname: Hong
authors.forename: Jung Jae
authors.initials: JJ
authors.lastname: Ko
authors.forename: Hyung Min
authors.initials: HM
authors.lastname: Chung
authors.forename: Kwang Yul
authors.initials: KY
authors.lastname: Cha
mesh_terms: D000328:Adult; D015925:Cryopreservation / Q000379:methods*; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007231:Infant, Newborn; D009865:Oocytes; D011247:Pregnancy; D020554:Sperm Injections, Intracytoplasmic