title: Effectiveness of two-step (consecutive) embryo transfer in patients who have two embryos on day 2: comparison with cleavage-stage embryo transfer.
abstract: OBJECTIVE
  To evaluate the effectiveness, for patients who have only two embryos on day 2, of a two-step (consecutive) embryo transfer (ET) procedure in which a cleaved embryo is transferred on day 2 and a single blastocyst is transferred on day 5.
  
  
  METHODS
  Observational comparative study.
  
  
  METHODS
  Private IVF clinic.
  
  
  METHODS
  Ninety two-step ET cycles were performed in patients who had two embryos on day 2 (two-step group). Ninety day-2 ET cycles were performed in age- and infertility-matched patients who had two embryos on day 2 (control group).
  
  
  METHODS
  Cleaved-ET, extended culture of one embryo, and a second transfer of a blastocyst.
  
  
  METHODS
  Implantation and pregnancy rates.
  
  
  RESULTS
  The pregnancy and implantation rates in the two-step group (respectively 33.3% and 17.2%) were significantly higher than those in the control group (18.9% and 9.4%). Thirty-nine of the patients in the two-step group (43.3%) could not proceed to the second step of ET because no viable blastocyst could be obtained, but four of them conceived anyway.
  
  
  CONCLUSIONS
  Taking advantage of both day-2 ET and blastocyst transfer, two-step ET may be an effective option for ET in patients who have an insufficient number of embryos.
authors.affiliation: Hanabusa Women's Clinic, Kobe, Hyogo, Japan. gotoms@tcn.zaq.ne.jp
authors.forename: Sakae
authors.initials: S
authors.lastname: Goto
authors.forename: Masahide
authors.initials: M
authors.lastname: Shiotani
authors.forename: Masaru
authors.initials: M
authors.lastname: Kitagawa
authors.forename: Takashi
authors.initials: T
authors.lastname: Kadowaki
authors.forename: Yoichi
authors.initials: Y
authors.lastname: Noda
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000166:cytology*; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007247:Infertility, Female / Q000628:therapy*; D011247:Pregnancy; D018873:Pregnancy Rate; D013997:Time Factors