title: Effect of age on the response of the hypothalamo-pituitary-ovarian axis to a combined oral contraceptive.
abstract: OBJECTIVE
  To examine the effect of age on the response to treatment with a combined oral contraceptive.
  
  
  METHODS
  Prospective, controlled clinical study.
  
  
  METHODS
  Reproductive medicine unit in a tertiary care university medical center.
  
  
  METHODS
  Twenty-six healthy female volunteers aged 21-45 years.
  
  
  METHODS
  After a control cycle, all the women were given a combined oral contraceptive containing 20 microg of ethinylestradiol with 75 microg of gestodene for three cycles. The women were examined through the posttreatment cycle.
  
  
  METHODS
  Pituitary and ovarian activity was assessed with ultrasound and measurement of ovarian steroids.
  
  
  RESULTS
  Follicular activity was observed in all treatment cycles, although ovulation was inhibited. Ovarian suppression was maximal in cycle 1. Mean endogenous E2 levels were lower during cycles 2 and 3 in the older group. Serum FSH levels were higher in the control cycle and on day 28 of the treatment cycles in the older group. Most women ovulated during the posttreatment cycle.
  
  
  CONCLUSIONS
  Combined oral contraceptives did not inhibit all ovarian activity; maximal suppression was seen in cycle 1. Less follicular activity was observed in cycles 2 and 3 in the older group. Raised FSH levels with age reflect increasing ovarian resistance to follicular development.
authors.affiliation: Department of Reproductive Medicine, University Hospital of South Manchester, United Kingdom.
authors.forename: C
authors.initials: C
authors.lastname: Fitzgerald
authors.forename: M
authors.initials: M
authors.lastname: Elstein
authors.forename: J
authors.initials: J
authors.lastname: Spona
mesh_terms: D000328:Adult; D000375:Aging; D003277:Contraceptives, Oral, Combined / Q000494:pharmacology*; D004958:Estradiol / Q000097:blood; D004997:Ethinyl Estradiol / Q000008:administration & dosage; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007031:Hypothalamus / Q000187:drug effects* / Q000502:physiology; D008875:Middle Aged; D009652:Norpregnenes / Q000008:administration & dosage; D010053:Ovary / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D010060:Ovulation; D010902:Pituitary Gland / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D011446:Prospective Studies; D014463:Ultrasonography
chemical_list: D003277:Contraceptives, Oral, Combined; D009652:Norpregnenes; C033273:Gestodene; D004997:Ethinyl Estradiol; D004958:Estradiol; D005640:Follicle Stimulating Hormone