title: eSET irrespective of the availability of a good-quality embryo in the first cycle only is not effective in reducing overall twin pregnancy rates.
abstract: BACKGROUND
  In several clinics, elective single-embryo transfer (eSET) is applied in a selected group of patients based on age and the availability of a good-quality embryo. Whether or not eSET can be applied irrespective of the presence of a good-quality embryo in the first cycle, to further reduce the twin pregnancy rate, remains to be elucidated.
  
  
  METHODS
  In patients <38 years two transfer strategies were compared, which differed in the first cycle only: group A (n = 141) received eSET irrespective of the availability of a good-quality embryo, and group B (n = 174) received eSET when a good-quality embryo was available while otherwise they received double embryo transfer (DET; referred to as eSET/DET transfer policy). In any subsequent cycle, in both groups the eSET/DET transfer policy was applied.
  
  
  RESULTS
  After completion of their IVF treatment (including a maximum of three fresh cycles and the transfer of frozen-thawed embryos), comparable cumulative live birth rates (62.4% in group A and 62.6% in group B) and twin pregnancy rates (10.1 versus 13.4%) were found. However, patients in group A required significantly more fresh (2.0 versus 1.8) and frozen (0.8 versus 0.5) cycles.
  
  
  CONCLUSIONS
  The transfer of one embryo in the first cycle, irrespective of the availability of a good-quality embryo, in all patients <38 years, is not an effective transfer policy for reducing the overall twin pregnancy rate.
authors.affiliation: Research Institute Growth & Development (GROW), Department of Obstetrics and Gynaecology, Academic Hospital Maastricht, PO Box 5800, 6202 AZ Maastricht, The Netherlands. avmn@sgyn.azm.nl
authors.forename: Aafke P A
authors.initials: AP
authors.lastname: van Montfoort
authors.forename: Audrey A A
authors.initials: AA
authors.lastname: Fiddelers
authors.forename: Jolande A
authors.initials: JA
authors.lastname: Land
authors.forename: Carmen D
authors.initials: CD
authors.lastname: Dirksen
authors.forename: Johan L
authors.initials: JL
authors.lastname: Severens
authors.forename: Joep P M
authors.initials: JP
authors.lastname: Geraedts
authors.forename: Johannes L H
authors.initials: JL
authors.lastname: Evers
authors.forename: John C M
authors.initials: JC
authors.lastname: Dumoulin
mesh_terms: D000328:Adult; D004624:Embryo Transfer; D004622:Embryo, Mammalian / Q000502:physiology*; D005260:Female; D006801:Humans; D011247:Pregnancy; D018873:Pregnancy Rate; D014427:Twins