title: Blastocyst transfer: a useful tool for reduction of high-order multiple gestations in a human assisted reproduction program.
abstract: OBJECTIVE
  We evaluated the efficacy of blastocyst transfer in decreasing the incidence of high-order multiple gestations after in vitro fertilization.
  
  
  METHODS
  We conducted a retrospective analysis of 218 patients who were undergoing in vitro fertilization and by our criteria of three 8-cell embryos on day 3 could receive either a day 3 transfer of cleaved embryos or a day 5 transfer of blastocysts. Ongoing pregnancy rates, implantation rates (determined by the total number of visualized gestational sacs), and multiple pregnancy rates were compared between the 2 groups.
  
  
  RESULTS
  Respective day 3 and day 5 ongoing pregnancy rates (61% and 51%) and implantation rates (35% and 33%) were not significantly different. There were 9 triplet or higher gestations in the day 3 group and 0 in the day 5 group.
  
  
  CONCLUSIONS
  Blastocyst transfer can be used to reduce the number of embryos transferred and the resultant incidence of high-order multiple pregnancies while maintaining high pregnancy rates.
authors.affiliation: Reproductive Biology Associates, Atlanta, GA 30342, USA.
authors.forename: A A
authors.initials: AA
authors.lastname: Toledo
authors.forename: G
authors.initials: G
authors.lastname: Wright
authors.forename: A E
authors.initials: AE
authors.lastname: Jones
authors.forename: S S
authors.initials: SS
authors.lastname: Smith
authors.forename: J
authors.initials: J
authors.lastname: Johnson-Ward
authors.forename: W W
authors.initials: WW
authors.lastname: Brockman
authors.forename: F
authors.initials: F
authors.lastname: Ng
authors.forename: J D
authors.initials: JD
authors.lastname: Wininger
mesh_terms: D000328:Adult; D001755:Blastocyst; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D011272:Pregnancy, Multiple; D012189:Retrospective Studies; D016896:Treatment Outcome