title: A simplified method of timing frozen embryo transfers.
abstract: OBJECTIVE
  Our purpose was to compare a simple artificial hormone replacement regimen with two other protocols incorporating pituitary down-regulation with gonadotropin-releasing hormone agonist for frozen embryo transfers.
  
  
  METHODS
  We performed a retrospective analysis of pregnancy outcomes after 366 frozen embryo transfers timed by one of three hormone replacement regimens. The three regimens used were regimen A, leuprolide acetate and transdermal estradiol patches; regimen B, leuprolide acetate and oral micronized estradiol; regimen C, only oral micronized estradiol.
  
  
  RESULTS
  The outcomes of 366 consecutive frozen embryo transfers according to one of the three regimens were compared and analyzed. The clinical pregnancy rates were 13.7%, 11.4% and 13.5% in regimens A, B and C, respectively. No statistical differences were found among the three regimens. The mean age of the patients in the three groups was comparable. The mean number of frozen embryos transferred with regimen B was slightly higher, but it did not have a positive impact on the pregnancy rate in this group.
  
  
  CONCLUSIONS
  Controlled sequential hormone replacement results in an endometrium suitable for frozen embryo transfers. Pituitary down-regulation is not necessary. Therefore this regimen is not only more simple to use but also more economical.
authors.affiliation: Department of Obstetrics and Gynecology, Long Beach Memorial Medical Center, University of California, Irvine, USA.
authors.forename: B
authors.initials: B
authors.lastname: Yee
authors.forename: Y P
authors.initials: YP
authors.lastname: Lin
authors.forename: R R
authors.initials: RR
authors.lastname: Chacon
authors.forename: S
authors.initials: S
authors.lastname: Soubra
authors.forename: G F
authors.initials: GF
authors.lastname: Rosen
authors.forename: D L
authors.initials: DL
authors.lastname: Cassidenti
mesh_terms: D015925:Cryopreservation; D004624:Embryo Transfer / Q000379:methods*; D004958:Estradiol / Q000008:administration & dosage / Q000627:therapeutic use; D005260:Female; D005307:Fertilization in Vitro; D015181:Gamete Intrafallopian Transfer; D006801:Humans; D016729:Leuprolide / Q000008:administration & dosage / Q000627:therapeutic use; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D004958:Estradiol; D016729:Leuprolide