title: The influence of sporadic anovulation on hormone levels in ovulatory cycles.
abstract: OBJECTIVE
  Do ovulatory hormone profiles among healthy premenopausal women differ between women with and without sporadic anovulation?
  
  
  CONCLUSIONS
  Women with one anovulatory cycle tended to have lower estradiol, progesterone and LH peak levels during their ovulatory cycle.
  
  
  BACKGROUND
  Anovulation occurs sporadically in healthy premenopausal women, but the influence of hormones in a preceding cycle and the impact on a subsequent cycle's hormone levels is unknown.
  
  
  METHODS
  The BioCycle Study was a prospective cohort including 250 healthy regularly menstruating women, 18-44 years of age, from Western New York with no history of menstrual or ovulation disorders. The women were followed with up to eight study visits per cycle for two cycles, most of which were consecutive.
  
  
  METHODS
  All study visits were timed to menstrual cycle phase using fertility monitors and located at the University at Buffalo women's health research center from 2005 to 2007. The main outcomes measured were estradiol, progesterone, LH and follicle-stimulating hormone levels in serum at up to 16 visits over two cycles. Anovulation was defined as peak serum progesterone concentrations ≤5 ng/ml and no serum LH peak detected during the mid- or late-luteal phase visit.
  
  
  RESULTS
  Reproductive hormone concentrations were lower during anovulatory cycles, but significant reductions were also observed in estradiol (-25%, P = 0.003) and progesterone (-22%, P = 0.001) during the ovulatory cycles of women with one anovulatory cycle compared with women with two ovulatory cycles. LH peak concentrations were decreased in the ovulatory cycle of women with an anovulatory cycle (significant amplitude effect, P = 0.004; geometric mean levels 38% lower, P < 0.05).
  
  
  CONCLUSIONS
  Follow-up was limited to two menstrual cycles, and no ultrasound assessment of ovulation was available. Data were missing for a total of 168 of a possible 4072 cycle visits (4.1%), though all women had at least five visits per cycle (94% had seven or more per cycle).
  
  
  CONCLUSIONS
  These results suggest a possible underlying cause of anovulation, such as a longer-term subclinical follicular, ovarian or hypothalamic/pituitary dysfunction, even among healthy, regularly menstruating women.
authors.affiliation: Epidemiology Branch, Division of Epidemiology, Statistics and Prevention Research, Eunice Kennedy Shriver National Institute of Child Health and Human Development, NIH, DHHS, Rockville, MD 20852, USA.
authors.forename: H L
authors.initials: HL
authors.lastname: Hambridge
authors.forename: S L
authors.initials: SL
authors.lastname: Mumford
authors.forename: D R
authors.initials: DR
authors.lastname: Mattison
authors.forename: A
authors.initials: A
authors.lastname: Ye
authors.forename: A Z
authors.initials: AZ
authors.lastname: Pollack
authors.forename: M S
authors.initials: MS
authors.lastname: Bloom
authors.forename: P
authors.initials: P
authors.lastname: Mendola
authors.forename: K L
authors.initials: KL
authors.lastname: Lynch
authors.forename: J
authors.initials: J
authors.lastname: Wactawski-Wende
authors.forename: E F
authors.initials: EF
authors.lastname: Schisterman
mesh_terms: D000293:Adolescent; D000328:Adult; D000858:Anovulation / Q000097:blood*; D015331:Cohort Studies; D004958:Estradiol / Q000097:blood*; D005260:Female; D006801:Humans; D016014:Linear Models; D007986:Luteinizing Hormone / Q000097:blood*; D010060:Ovulation / Q000097:blood / Q000502:physiology; D011374:Progesterone / Q000097:blood*
chemical_list: D011374:Progesterone; D004958:Estradiol; D007986:Luteinizing Hormone
keywords: anovulation; menstrual cycle; sex hormones