title: Similar endometrial development in oocyte donors treated with either high- or standard-dose GnRH antagonist compared to treatment with a GnRH agonist or in natural cycles.
abstract: BACKGROUND
  This descriptive study evaluates the impact on endometrial development of standard and high doses of a GnRH antagonist in stimulated cycles compared with GnRH agonist and natural cycles.
  
  
  METHODS
  Thirty-one oocyte donors were treated with a combination of rFSH and 0.25 mg/day ganirelix (standard dose), 2 mg/day ganirelix (high dose) or 0.6 mg/day buserelin (long protocol). Vaginal progesterone (200 mg/day) was administered in the luteal phase. Endometrial biopsies were performed 2 and 7 days after HCG administration. Additional biopsies were carried out in a subset of 12 subjects, 2 and 7 days following the LH peak of their previous natural cycle. Biopsies were evaluated histologically and by scanning electron microscopy. Gene expression profiles were also studied.
  
  
  RESULTS
  At HCG +2, all the parameters studied were similar in all the groups and comparable to those observed in the natural cycle. At HCG +7, endometrial dating, steroid receptors and the presence of pinopodes were comparable in both GnRH antagonist groups and in the natural cycle. In buserelin group, endometrial dating and pinopode expression suggested an arrested endometrial development. For window of implantation genes, expression patterns were closer to those in the natural cycle following standard- or high-dose ganirelix than after buserelin administration.
  
  
  CONCLUSIONS
  No relevant alteration was observed in the endometrial development in the early and mid-luteal phases in women undergoing controlled ovarian stimulation for oocyte donation following daily treatment with a standard- or high-dose GnRH antagonist. In addition, the endometrial development after GnRH antagonist mimics the natural endometrium more closely than after GnRH agonist.
authors.affiliation: Instituto Valenciano de Infertilidad Foundation (FIVI)-University of Valencia, Instituto Valenciano de Infertilidad (IVI), Valencia, Spain. csimon@ivi.es
authors.forename: C
authors.initials: C
authors.lastname: Simon
authors.forename: J
authors.initials: J
authors.lastname: Oberyé
authors.forename: J
authors.initials: J
authors.lastname: Bellver
authors.forename: C
authors.initials: C
authors.lastname: Vidal
authors.forename: E
authors.initials: E
authors.lastname: Bosch
authors.forename: J A
authors.initials: JA
authors.lastname: Horcajadas
authors.forename: C
authors.initials: C
authors.lastname: Murphy
authors.forename: S
authors.initials: S
authors.lastname: Adams
authors.forename: A
authors.initials: A
authors.lastname: Riesewijk
authors.forename: B
authors.initials: B
authors.lastname: Mannaerts
authors.forename: A
authors.initials: A
authors.lastname: Pellicer
mesh_terms: D000293:Adolescent; D000328:Adult; D002064:Buserelin / Q000494:pharmacology; D006063:Chorionic Gonadotropin; D004717:Endometrium / Q000166:cytology* / Q000187:drug effects / Q000473:pathology; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000627:therapeutic use; D005786:Gene Expression Regulation; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists* / Q000031:analogs & derivatives / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D006801:Humans; D008183:Luteal Phase; D008855:Microscopy, Electron, Scanning; D020411:Oligonucleotide Array Sequence Analysis; D018587:Oocyte Donation / Q000379:methods*; D009865:Oocytes / Q000166:cytology* / Q000378:metabolism / Q000473:pathology; D010062:Ovulation Induction; D012313:RNA / Q000737:chemistry; D011960:Receptors, Estrogen / Q000378:metabolism; D011980:Receptors, Progesterone / Q000378:metabolism; D013997:Time Factors; D014465:Ultrasonics
chemical_list: D006063:Chorionic Gonadotropin; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D007987:Gonadotropin-Releasing Hormone; D012313:RNA; D005640:Follicle Stimulating Hormone; C061018:ganirelix; D002064:Buserelin