title: Defining poor ovarian response during IVF cycles, in women aged <40 years, and its relationship with treatment outcome.
abstract: BACKGROUND
  Poor ovarian response limits IVF success but assessing interventions is difficult because of the wide variation in definition. This study attempts to derive objective definitions of poor response.
  
  
  METHODS
  A retrospective study of a consecutive series of 1190 patients aged <40 years undergoing their first IVF/ICSI cycle was undertaken. Factors adversely affecting implantation, including advanced female age, were excluded. Clinical outcome in cycles reaching oocyte retrieval (n = 1036) were evaluated with respect to gonadotrophin dose used and oocyte number. Cancelled cycles (n = 154) were analysed in relation to the stimulation dose at cancellation and outcome of their subsequent cycle.
  
  
  RESULTS
  Cycle cancellation for patients on >/=300 IU FSH/day compared to those on a lower dose was associated with a significantly worse outcome in the subsequent cycle. If <3000 IU FSH/cycle were administered, clinical pregnancy rates remained favourable if <4 eggs were recovered (29 versus 33% for >/=5 eggs). By contrast, if >/=3000 IU FSH was required, the pregnancy rate was 25% if >/=5 eggs were recovered but declined to 7% if <4 were obtained.
  
  
  CONCLUSIONS
  Definitions of poor response should include the degree of ovarian stimulation used. A low oocyte number is only detrimental if the cumulative dose is >3000 IU FSH. Cancellation at >/=300 IU FSH/day is associated with a significantly worse prognosis and could define poor response.
authors.affiliation: University of Bristol, St Michael's Hospital, Bristol, BS2 8EG, UK. Chandra.Kailasam@repromed-bristol.co.uk
authors.forename: C
authors.initials: C
authors.lastname: Kailasam
authors.forename: S D
authors.initials: SD
authors.lastname: Keay
authors.forename: P
authors.initials: P
authors.lastname: Wilson
authors.forename: W C L
authors.initials: WC
authors.lastname: Ford
authors.forename: J M
authors.initials: JM
authors.lastname: Jenkins
mesh_terms: D000328:Adult; D000375:Aging; D004305:Dose-Response Relationship, Drug; D005260:Female; D005307:Fertilization in Vitro; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D009865:Oocytes; D010053:Ovary / Q000187:drug effects / Q000502:physiology*; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D020858:Tissue and Organ Harvesting; D016896:Treatment Outcome
chemical_list: D005640:Follicle Stimulating Hormone