title: The LH/FSH ratio has little use in diagnosing polycystic ovarian syndrome.
abstract: BACKGROUND
  The luteinizing hormone/follicle stimulating hormone (LH/FSH) ratio is often requested to help diagnose polycystic ovarian syndrome (PCOS) despite a recent consensus recommending against its use. This study aimed to compare the variability of the LH/FSH ratio in PCOS with that of normal menstruating women over a full cycle in order to establish the diagnostic utility, or otherwise, of the test.
  
  
  METHODS
  Twelve women with PCOS and 11 matched controls had blood collected at four-day intervals on 10 consecutive occasions over a complete menstrual cycle.
  
  
  RESULTS
  The median LH/FSH ratio for individual subjects did not differ significantly between the PCOS and the non-affected group (1.6 versus 1.2, P = 0.14). Only 7.6% of samples from PCOS patients had an LH/FSH ratio above three, compared with 15.6% of samples from normal subjects.
  
  
  CONCLUSIONS
  This study confirms that measurement of the LH/FSH ratio is of limited use in the diagnosis of PCOS.
authors.affiliation: Department of Medicine, University of Hull, Hull, UK. L.Cho@hull.ac.uk
authors.forename: Li Wei
authors.initials: LW
authors.lastname: Cho
authors.forename: Vijay
authors.initials: V
authors.lastname: Jayagopal
authors.forename: Eric S
authors.initials: ES
authors.lastname: Kilpatrick
authors.forename: Stephen
authors.initials: S
authors.lastname: Holding
authors.forename: Stephen L
authors.initials: SL
authors.lastname: Atkin
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood*; D006801:Humans; D007986:Luteinizing Hormone / Q000097:blood*; D008597:Menstrual Cycle; D011085:Polycystic Ovary Syndrome / Q000175:diagnosis*; D011379:Prognosis
chemical_list: D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone