title: Ganirelix acetate causes a rapid reduction in estradiol levels without adversely affecting oocyte maturation in women pretreated with leuprolide acetate who are at risk of ovarian hyperstimulation syndrome.
abstract: BACKGROUND
  Elevated estradiol (E(2)) levels predispose to development of ovarian hyperstimulation syndrome (OHSS). Since GnRH antagonist is associated with a reduction in E(2) levels, we hypothesized that GnRH-antagonist treatment of women down-regulated with GnRH agonist who are at risk of OHSS might reduce E(2) levels and avoid cycle cancellation.
  
  
  METHODS
  Retrospective study in a university-based assisted reproduction technology (ART) programme in 87 patients treated with long luteal (LL) or microdose flare (MDF) with ovarian hyperresponse and 87 control patients without ovarian hyperresponse. GnRH-antagonist (ganirelix acetate) treatment was started and leuprolide acetate discontinued in women who failed to respond to a reduction in gonadotrophin dosage.
  
  
  RESULTS
  In the treatment group, there was a significant, reproducible reduction in serum E(2) levels. Mean E(2) at the start of ganirelix treatment was 4219.8 pg/ml and decreased in 24 h to 2613.7 pg/ml (36.7%; P < 0.001). An average of 24.9 +/- 8.8 oocytes were obtained at retrieval and an average of 19.1 +/- 8.0 were metaphase II (79.2%). Fertilization occurred in 13.9 +/- 8.1 embryos (72.8%). In this high risk group, two cases of severe OHSS (2.3%) occurred. The ongoing pregnancy rate was 51.8%. Compared with the control group, there were no statistically significant differences in the rate of oocyte recovery, oocyte maturity, 2PN rate, fertilization, cancellation, OHSS or pregnancy.
  
  
  CONCLUSIONS
  GnRH-antagonist treatment of women pretreated with GnRH agonist rapidly reduced circulating serum E(2) without adversely affecting oocyte maturation, fertilization rates or embryo quality and resulted in a high pregnancy rate in this subgroup of patients at risk of OHSS.
authors.affiliation: Reproductive Endocrinology and Infertility, NIH, Bethesda, MD, USA.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Gustofson
authors.forename: James H
authors.initials: JH
authors.lastname: Segars
authors.forename: Frederick W
authors.initials: FW
authors.lastname: Larsen
mesh_terms: D000328:Adult; D004958:Estradiol / Q000097:blood*; D005260:Female; D005300:Fertility Agents, Female / Q000627:therapeutic use; D005306:Fertilization; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives* / Q000494:pharmacology; D006727:Hormone Antagonists / Q000494:pharmacology*; D006801:Humans; D016729:Leuprolide / Q000627:therapeutic use*; D009865:Oocytes / Q000187:drug effects / Q000502:physiology*; D016471:Ovarian Hyperstimulation Syndrome / Q000517:prevention & control*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012016:Reference Values; D012189:Retrospective Studies
chemical_list: D005300:Fertility Agents, Female; D006727:Hormone Antagonists; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D016729:Leuprolide; C061018:ganirelix