title: The effect of danazol on pulsatile gonadotropin secretion in women with endometriosis.
abstract: OBJECTIVE
  To determine whether the effect of danazol on gonadotropin pulsatility was due to a direct effect of the drug or the suppression in the estradiol (E2) levels.
  
  
  METHODS
  Prospective analysis of serial blood samples at 10-minute intervals for 5 hours on days 3, 4, or 5 of the control cycle and 2 months after the start of danazol treatment.
  
  
  METHODS
  Tertiary institutional outpatient care.
  
  
  METHODS
  Six eugonadal women with minimal endometriosis.
  
  
  METHODS
  Oral administration of danazol, 200 mg three times daily.
  
  
  METHODS
  Gonadotropin mean levels, pulse frequency, and amplitude.
  
  
  RESULTS
  The mean level of E2 was the same in the control cycle as that during danazol treatment (170 pmol/L). Danazol administration resulted in a 16% increase in the mean luteinizing hormone (LH) pulse amplitude (95% confidence interval [CI] 6% to 26%, P less than 0.01), associated with a 20% decrease in LH pulse frequency (95% CI -71% to +31%, P = 0.37). There was a nonsignificant increase in follicle-stimulating hormone (FSH) pulse amplitude (2%, 95% CI -9% to +14%, P = 0.68) and in FSH pulse frequency (27%, 95% CI -4% to +58%, P = 0.08). The 22% decrease in the mean LH level (95% CI -85% to +12%, P = 0.13) and the 20% decrease in the mean FSH level (95% CI -53% to +37%, P = 0.33) were also not significant.
  
  
  CONCLUSIONS
  The increase in LH pulse amplitude represents a direct effect of danazol on the hypothalamic-pituitary axis.
authors.affiliation: Queen Charlotte's Hospital, London, United Kingdom.
authors.forename: P
authors.initials: P
authors.lastname: Maouris
authors.forename: M
authors.initials: M
authors.lastname: Dowsett
authors.forename: D K
authors.initials: DK
authors.lastname: Edmonds
authors.forename: D
authors.initials: D
authors.lastname: Sullivan
mesh_terms: D000328:Adult; D003613:Danazol / Q000494:pharmacology*; D004715:Endometriosis / Q000503:physiopathology*; D004958:Estradiol / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism*; D006801:Humans; D007986:Luteinizing Hormone / Q000378:metabolism*; D010507:Periodicity
chemical_list: D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone; D003613:Danazol