title: Effects of clomiphene citrate on pituitary luteinizing hormone and follicle-stimulating hormone release in women before and after treatment with ethinyl estradiol.
abstract: OBJECTIVE
  To evaluate the effects of clomiphene citrate (CC) on pituitary luteinizing hormone (LH) and follicle-stimulating hormone (FSH) release in hypoestrogenic women and in the same women after treatment with ethinyl estradiol (EE2).
  
  
  METHODS
  The study was of a prospective nature and was conducted on selected patients.
  
  
  METHODS
  Volunteer women were studied in a tertiary care public hospital.
  
  
  METHODS
  The 10 patients studied were selected on the basis of hypogonadal status (menopause, premature ovarian failure, or gonadal dysgenesis and Turner phenotype) and no hormonal treatment.
  
  
  METHODS
  Gonadotropin-releasing hormone (GnRH) was continually infused at the dose of 0.2 micrograms/min for 4 hours before and after the use of CC and/or EE2.
  
  
  METHODS
  The study was performed with the objective of determining the effect of estrogen (E) levels on the action of CC on in vivo gonadotropin release.
  
  
  RESULTS
  In the presence of hypoestrogenic conditions, CC had no pituitary action. However, after EE2 treatment CC promoted greater FSH release and a significant inhibition of LH release from the pituitary.
  
  
  CONCLUSIONS
  Clomiphene citrate needs a basal E level to be able to act on the pituitary. In normoestrogenic states and under GnRH stimulation, CC preferentially promotes FSH release while presenting a predominantly inhibitory effect on LH release.
authors.affiliation: Department of Gynecology and Obstetrics, Faculty of Medicine of Ribeirão Preto, University of São Paulo, Brazil.
authors.forename: M D
authors.initials: MD
authors.lastname: de Moura
authors.forename: R A
authors.initials: RA
authors.lastname: Ferriani
authors.forename: M F
authors.initials: MF
authors.lastname: de Sá
mesh_terms: D002996:Clomiphene / Q000494:pharmacology*; D004997:Ethinyl Estradiol / Q000494:pharmacology*; D005260:Female; D005640:Follicle Stimulating Hormone / Q000378:metabolism*; D007987:Gonadotropin-Releasing Hormone; D006801:Humans; D007986:Luteinizing Hormone / Q000378:metabolism*; D010903:Pituitary Gland, Anterior / Q000187:drug effects / Q000378:metabolism*; D011446:Prospective Studies
chemical_list: D002996:Clomiphene; D007987:Gonadotropin-Releasing Hormone; D004997:Ethinyl Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone