title: Dose-finding study of daily GnRH antagonist for the prevention of premature LH surges in IVF/ICSI patients: optimal changes in LH and progesterone for clinical pregnancy.
abstract: BACKGROUND
  An optimal range of LH concentrations for achieving pregnancy has not been established. The aim of this study was to investigate the effect of various LH levels induced by different GnRH antagonist doses on IVF outcome.
  
  
  METHODS
  This was a prospective, single centre study including 144 IVF patients, stimulated with recombinant FSH from cycle day 2, and co-treated with daily GnRH antagonist (antide/Iturelix) (2 mg/2 ml, 1 mg/ml, 0.5 mg/ml, 0.5 mg/0.5 ml or 0.25 mg/ml) from cycle day 7 onwards. Serum samples were taken three times daily.
  
  
  RESULTS
  Clinical pregnancies were only observed within a particular range of change in LH levels. The upper and lower thresholds for the mean LH area under the curve (AUC), adjusted for the baseline LH level before the antagonist was started (LH AUC(-S6); S6=stimulation day 6) were -2.2 and 12.4 (IU/l) respectively (a negative value=below baseline levels). There were no clinical pregnancies outside these threshold values. Similar results were found for progesterone, the threshold levels of progesterone AUC(-S6) were 3.98 and -1.21 ng/ml. Moreover, there were no pregnancies with progesterone levels >0.26 ng/ml/follicle on the day of hCG.
  
  
  CONCLUSIONS
  Excessive or insufficient suppression of LH and progesterone levels during GnRH antagonist administration and high progesterone/follicle on hCG day seems to be associated with impaired clinical pregnancy rates.
authors.affiliation: Division of Reproductive Medicine, Department of Obstetrics and Gynaecology, Vrije Universiteit Medical Centre, Amsterdam, The Netherlands.
authors.forename: Judith A F
authors.initials: JA
authors.lastname: Huirne
authors.forename: Andre C D
authors.initials: AC
authors.lastname: van Loenen
authors.forename: Roel
authors.initials: R
authors.lastname: Schats
authors.forename: Joseph
authors.initials: J
authors.lastname: McDonnell
authors.forename: Peter G A
authors.initials: PG
authors.lastname: Hompes
authors.forename: Joop
authors.initials: J
authors.lastname: Schoemaker
authors.forename: Roy
authors.initials: R
authors.lastname: Homburg
authors.forename: Cornelis B
authors.initials: CB
authors.lastname: Lambalk
mesh_terms: D000328:Adult; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D007987:Gonadotropin-Releasing Hormone / Q000037:antagonists & inhibitors; D006727:Hormone Antagonists / Q000008:administration & dosage*; D006801:Humans; D007247:Infertility, Female / Q000097:blood / Q000188:drug therapy*; D007986:Luteinizing Hormone / Q000097:blood*; D009842:Oligopeptides / Q000008:administration & dosage*; D011247:Pregnancy; D011256:Pregnancy Outcome; D011374:Progesterone / Q000097:blood*; D011446:Prospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000379:methods
chemical_list: D006727:Hormone Antagonists; D009842:Oligopeptides; D007987:Gonadotropin-Releasing Hormone; D011374:Progesterone; D007986:Luteinizing Hormone; C057022:iturelix