title: Assisted reproduction using donated embryos: outcomes from surveillance systems in six countries.
abstract: BACKGROUND
  Embryo donation, though less often performed than other assisted reproductive technology (ART), can represent an attractive option for couples who do not wish to discard their embryos remaining after IVF, and for those who cannot or should not conceive naturally. Clinicians and potential participants could benefit from information comparing outcomes of embryo donation with those of other ARTs, in various countries.
  
  
  METHODS
  We analyzed outcome information from ART treatment cycles using 2001-2008 data from national surveillance systems in the USA, Canada, the UK, Australia, New Zealand and Finland. We calculated the live birth rate (LBR) with relative risks, the average number of embryos transferred per cycle and the ratio between them (LBR per embryo transferred). We compared outcomes of embryo donation cycles with those for autologous IVF, frozen embryo transfer (FET) and oocyte donation (OD).
  
  
  RESULTS
  LBRs for embryo donation cycles were 14-33%, compared with 16-28% for autologous FET, 22-35% for autologous IVF and 15-52% for OD. In every country except Australia/New Zealand, and in all countries combined, the LBR for embryo donation approximated that for IVF, with no statistically significant differences in Finland and Canada. The average number of embryos transferred per cycle was 1.5-2.8. The LBR per embryo transferred was 11-12% for donor embryo cycles, compared with 8-11% for autologous FET, 12-15% for autologous IVF and 9-21% for OD.
  
  
  CONCLUSIONS
  We found that transfer of donated embryos in these countries yields pregnancy outcomes comparable to those of autologous ART procedures. The variation in outcome rates among countries is not entirely explained by the number of embryos transferred. The relatively high success rates and low costs make embryo donation an attractive family building alternative.
authors.affiliation: National Embryo Donation Center, 11126 Kingston Pike, Knoxville, TN 37934,  USA.
authors.forename: Jeffrey A
authors.initials: JA
authors.lastname: Keenan
authors.forename: Mika
authors.initials: M
authors.lastname: Gissler
authors.forename: Reginald
authors.initials: R
authors.lastname: Finger
mesh_terms: D000328:Adult; D001315:Australia; D001723:Birth Rate; D001755:Blastocyst; D002170:Canada; D004624:Embryo Transfer; D005260:Female; D005387:Finland; D006801:Humans; D007246:Infertility; D008297:Male; D009520:New Zealand; D027724:Reproductive Techniques, Assisted; D009927:Tissue and Organ Procurement; D016896:Treatment Outcome; D006113:United Kingdom; D014481:United States