title: Use of the CryoPredict algorithm to predict live birth from cryopreserved embryos.
abstract: BACKGROUND
  Currently, the viability of cryostored blastocysts that are subsequently re-warmed is determined via the percentage of cell survival. However, the large number of cells that forms the blastocyst can make this estimate difficult and unreliable. Studies have shown that fast re-expanding blastocysts have superior pregnancy rates.
  
  
  OBJECTIVE
  To determine whether the degree and speed of blastocoele re-expansion following cryopreservation and warming correlate with rates of live birth.
  
  
  METHODS
  A retrospective cohort study of 757 frozen embryo transfer cycles over a 4-year period at Royal Prince Alfred Hospital, Sydney. Clinical and embryology notes were retrieved. Details regarding patient demographics, stimulation cycle from which embryos were derived, frozen embryo transfer cycles, embryology and pregnancy outcomes were recorded.
  
  
  RESULTS
  Female (P = 0.01) and male age (P = 0.02) at the time of embryo creation were inversely associated with live birth. Fertilisation method (P = 0.03), embryo type at cryopreservation (P = 0.009), embryo grade at cryopreservation (P < 0.0001), percentage of cell survival post-thaw (P < 0.0001) and the degree of re-expansion (P = 0.003) were the IVF and embryology factors significantly associated with live birth. A predictive model (CryoPredict) was created in order to individualise the probability that the transfer of a given embryo would result in live birth.
  
  
  CONCLUSIONS
  The degree and speed of blastocoele re-expansion postcryopreservation and subsequent warming can be used in conjunction with other parameters to predict live birth.
authors.affiliation: Department of Reproductive Endocrinology and Infertility, Royal Prince Alfred Hospital for Women and Babies, Camperdown, New South Wales, Australia.|Genea Fertility, Sydney, New South Wales, Australia.|Queen Elizabeth II Research Institute for Mothers and Infants, Department of Obstetrics, Gynaecology and Neonatology, The University of Sydney, Sydney, New South Wales, Australia.
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Marren
authors.affiliation: Department of Reproductive Endocrinology and Infertility, Royal Prince Alfred Hospital for Women and Babies, Camperdown, New South Wales, Australia.|Genea Fertility, Sydney, New South Wales, Australia.
authors.forename: Ying Ying
authors.initials: YY
authors.lastname: Tan
authors.affiliation: Queen Elizabeth II Research Institute for Mothers and Infants, Department of Obstetrics, Gynaecology and Neonatology, The University of Sydney, Sydney, New South Wales, Australia.|Department of Obstetrics and Gynaecology, Royal Prince Alfred Hospital for Women and Babies, Camperdown, New South Wales, Australia.
authors.forename: Bradley S
authors.initials: BS
authors.lastname: de Vries
authors.affiliation: Queen Elizabeth II Research Institute for Mothers and Infants, Department of Obstetrics, Gynaecology and Neonatology, The University of Sydney, Sydney, New South Wales, Australia.|Department of Obstetrics and Gynaecology, Royal Prince Alfred Hospital for Women and Babies, Camperdown, New South Wales, Australia.
authors.forename: Cecilia H M
authors.initials: CH
authors.lastname: Ng
authors.affiliation: Department of Reproductive Endocrinology and Infertility, Royal Prince Alfred Hospital for Women and Babies, Camperdown, New South Wales, Australia.|Genea Fertility, Sydney, New South Wales, Australia.
authors.forename: Mark
authors.initials: M
authors.lastname: Livingstone
authors.affiliation: Department of Reproductive Endocrinology and Infertility, Royal Prince Alfred Hospital for Women and Babies, Camperdown, New South Wales, Australia.|Genea Fertility, Sydney, New South Wales, Australia.
authors.forename: Mark C
authors.initials: MC
authors.lastname: Bowman
mesh_terms: D000328:Adult; D000367:Age Factors; D000465:Algorithms; D001755:Blastocyst; D002470:Cell Survival; D015925:Cryopreservation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods; D005544:Forecasting / Q000379:methods; D006801:Humans; D050498:Live Birth; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
keywords: blastocoele; cryopreservation; live birth and CryoPredict; re-expansion