title: Vitrification technology in whole embryo freezing.
abstract: OBJECTIVE
  To investigate the clinical outcome of patients who underwent whole embryo vitrification freezing and thawed frozen embryo transplantation, and to compare it with the patients at the same period in the fresh cycle to explore the value of vitrification technology in the whole embryo freezing combined with recovery transplantation.
  
  
  METHODS
  The whole embryo freezing group included 40 untransplanted cases of in-vitro fertilization (IVF), while another 300 patients in the fresh cycle with in vitro fertilization and embryo transfer (IVF-ET) at the same period served as the fresh cycle group. The average number of transferred embryos, high-quality embryos, endometrial thickness, estradiol (E₂) level, and clinical pregnancy rate were compared.
  
  
  RESULTS
  The average number of transferred embryos, high-quality embryos, difference in endometrial thickness were not significant between the 2 groups (P>0.05); the E₂ level of the fresh cylcle group was significantly higher than that of the whole embryo freezing group (P<0.05), and the clinical pregnancy rate in the fresh cylcle group was significantly lower than that of the whole embryo freezing group (P<0.05).
  
  
  CONCLUSIONS
  Vitrification technology is a simple, reliable, and efficient embryo freezing technology. For patients who meet the requirements, whole embryo vitrfication freezing and thawed frozen embryo transplantation is feasible. It is worth for further clinical research.
authors.affiliation: Maternal and Child Health Care Hospital, Nanjing Medical University, Wuxi Jiangsu 214002, China. xxd3100@163.com
authors.forename: Xiaodong
authors.initials: X
authors.lastname: Xie
authors.forename: Lian
authors.initials: L
authors.lastname: Zou
authors.forename: Yang
authors.initials: Y
authors.lastname: Shen
authors.forename: Fang
authors.initials: F
authors.lastname: Xiong
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
mesh_terms: D001755:Blastocyst / Q000166:cytology / Q000502:physiology; D015925:Cryopreservation / Q000379:methods*; D004624:Embryo Transfer / Q000379:methods*; D004622:Embryo, Mammalian / Q000378:metabolism / Q000502:physiology*; D047108:Embryonic Development; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D011247:Pregnancy; D058989:Vitrification