title: [Analysis of factors influencing the clinical in a frozen thawed embryo transfer program].
abstract: OBJECTIVE
  To analyze the factors influencing the outcome in a frozen thawed embryo transfer (FTET) program.
  
  
  METHODS
  Sixty FTET cycles performed in 53 cases from September 1997 to May 2000 were analyzed retrospectively. The related parameters were compared between the conceived and non-conceived cycles.
  
  
  RESULTS
  One hundred and seventy eight out of 252 thawed embryos were survival. Embryo transfers were undergone in 57 cycles (53 patients), resulting in 17 pregnancies (30% per transfer or 28% per thawed cycle). There were no significant difference between conceived and non-conceived cycles in terms of the controlled ovarian hyperstimulation protocols, numbers of developed follicle and oocyte retrieved, fertilization rate, numbers of frozen embryo and the luteinizing hormone, estradiol, progesterone levels on human chorionic gonadotropin triggering day. The percentage of good quality embryo before freezing and after thawing and survival thawed embryos were higher in conceived cycles than those in non-conceived cycles (83.8% Vs 60.7%, 76.8% Vs 50.0%, 82.4% Vs 66.3%, respectively P < 0.05).
  
  
  CONCLUSIONS
  Good quality of frozen-thawed embryos and the trilaminar sonographic pattern of endometrium may be reliable predictors of success in pregnancy.
authors.affiliation: Department of Gynecology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou 310006, China.
authors.forename: Y
authors.initials: Y
authors.lastname: Zhu
authors.forename: H
authors.initials: H
authors.lastname: Huang
authors.forename: F
authors.initials: F
authors.lastname: Zhou
mesh_terms: D015925:Cryopreservation / Q000592:standards; D004624:Embryo Transfer / Q000592:standards; D005260:Female; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate