title: Successful ongoing pregnancies after vitrification of oocytes.
abstract: OBJECTIVE
  To demonstrate the efficiency of vitrifying mature human oocytes for different clinical indications.
  
  
  METHODS
  Descriptive case series.
  
  
  METHODS
  Cryobiology laboratory, Centro Colombiano de Fertilidad y Esterilidad-CECOLFES LTDA. (Bogotá, Colombia).
  
  
  METHODS
  Oocyte vitrification was offered as an alternative management for patients undergoing infertility treatment because of ovarian hyperstimulation syndrome, premature ovarian failure, natural ovarian failure, male factor, poor response, or oocyte donation. Mature oocytes were obtained from 33 donor women and 40 patients undergoing infertility treatment.
  
  
  METHODS
  Oocytes were retrieved by ultrasound-guided transvaginal aspiration and vitrified with the Cryotops method, with 30% ethylene glycol, 30% dimethyl sulfoxide, and 0.5 mol/L sucrose. Viability was assessed 3 hours after thawing. The surviving oocytes were inseminated by intracytoplasmic sperm injection. Fertilization was evaluated after 24 hours. The zygotes were further cultured in vitro for up to 72 hours until time of embryo transfer.
  
  
  METHODS
  Recovery, viability, fertilization, and pregnancy rates.
  
  
  RESULTS
  Oocyte vitrification with the Cryotop method resulted in high rates of recovery, viability, fertilization, cleavage, and ongoing pregnancy.
  
  
  CONCLUSIONS
  Vitrification with the Cryotop method is an efficient, fast, and economical method for oocyte cryopreservation that offers high rates of survival, fertilization, embryo development, and ongoing normal pregnancies, providing a new alternative for the management of female infertility.
authors.affiliation: Centro Colombiano de Fertilid y Esterilidad-CECOLFES LTDA., Bogotá, Colombia. cecolfes@colomsat.net.co
authors.forename: Elkin
authors.initials: E
authors.lastname: Lucena
authors.forename: Diana Patricia
authors.initials: DP
authors.lastname: Bernal
authors.forename: Carolina
authors.initials: C
authors.lastname: Lucena
authors.forename: Alejandro
authors.initials: A
authors.lastname: Rojas
authors.forename: Abby
authors.initials: A
authors.lastname: Moran
authors.forename: Andrés
authors.initials: A
authors.lastname: Lucena
mesh_terms: D000328:Adult; D002470:Cell Survival; D015925:Cryopreservation / Q000379:methods*; D005260:Female; D006801:Humans; D009865:Oocytes / Q000166:cytology*; D016471:Ovarian Hyperstimulation Syndrome / Q000628:therapy*; D011247:Pregnancy; D018873:Pregnancy Rate; D016649:Primary Ovarian Insufficiency / Q000628:therapy*; D020554:Sperm Injections, Intracytoplasmic; D014015:Tissue Banks