title: Controlled ovarian hyperstimulation adversely affects implantation following in vitro fertilization-embryo transfer.
abstract: OBJECTIVE
  Our purpose was to determine if controlled ovarian hyperstimulation adversely affects implantation.
  
  
  METHODS
  A retrospective comparison of pregnancy rates (PRs) and implantation rates was made between oocyte recipients versus their donors, who shared half of the retrieved oocytes, and regular patients undergoing in vitro fertilization-embryo transfer (IVF-ET) who were not sharing eggs.
  
  
  RESULTS
  Higher implantation rates (39.0 vs 22.5%; P < 0.05) were found in recipients compared to donors in the stimulated cycle. However, no differences were seen in PRs or implantation rates in frozen ET cycles. The data for standard IVF patients were almost-identical to those for donors.
  
  
  CONCLUSIONS
  Superior implantation rates and PRs in oocyte recipients versus donors were not related to better oocyte quality for recipients because of egg sharing or to a better uterine environment because of similar results with frozen ET in all three groups. An adverse effect of the hyperstimulation regimen best explains the difference.
authors.affiliation: University of Medicine and Dentistry of New Jersey, Robert Wood Johnson Medical School at Camden, Cooper Hospital/University Medical Center, Department of Obstetrics and Gynecology, New Jersey, USA.
authors.forename: J H
authors.initials: JH
authors.lastname: Check
authors.forename: J K
authors.initials: JK
authors.lastname: Choe
authors.forename: D
authors.initials: D
authors.lastname: Katsoff
authors.forename: D
authors.initials: D
authors.lastname: Summers-Chase
authors.forename: C
authors.initials: C
authors.lastname: Wilson
mesh_terms: D000328:Adult; D010064:Embryo Implantation; D004624:Embryo Transfer; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D009865:Oocytes; D010062:Ovulation Induction / Q000009:adverse effects*; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies