title: The endocrine and follicular growth dynamics throughout the menstrual cycle in women with consistently or variably elevated early follicular phase FSH compared with controls.
abstract: BACKGROUND
  Elevated early follicular phase (EFP) FSH is frequently observed in subfertile patients. In these women, temporary normalization of FSH concentrations is known to occur. We studied the complete endocrine cycle profile of subfertile young women with elevated basal FSH compared with controls. METHODS Daily bloodsampling and ultrasound monitoring in the follicular phase was performed in 22 patients with elevated basal FSH levels (identified in screening) and in 16 controls during one menstrual cycle and for 5 days of the next cycle.
  
  
  RESULTS
  Eleven patients showed elevated basal FSH levels in the study cycle ('High, High'; H,H group) whereas 11 had normalized basal FSH levels ('High, Low'; H,L group). Anti-Müllerian hormone (AMH) was lower in both groups. In the H,H group, FSH was higher in all phases of the cycle and both inhibin A and B were lower during the EFP. In the H,L group, FSH was also higher than in controls in the EFP and the late luteal phase and inhibin A was higher in the periovulatory phase. 'Normalization' of Day 3 FSH in women with previously elevated FSH was associated with normalization of inhibin B levels in the preceding luteal phase.
  
  
  CONCLUSIONS
  The endocrine cycle profile in younger subfertile patients with consistently elevated basal FSH resembles that in published data from older women and also reflects a low ovarian reserve. Normalization of FSH in association with normal inhibin B suggests a temporary increase of the available cohort.
authors: Division of Reproductive Medicine, Department of Obstetrics and Gynaecology, Vrije Universiteit Medical Centre, PO Box 7057, 1007 MB Amsterdam, The Netherlands. rbcdk@xs4all.nl
authors: C H
authors: CH
authors: de Koning
authors: J
authors: J
authors: McDonnell
authors: A P N
authors: AP
authors: Themmen
authors: F H
authors: FH
authors: de Jong
authors: R
authors: R
authors: Homburg
authors: C B
authors: CB
authors: Lambalk
mesh_terms: D000328:Adult; D054304:Anti-Mullerian Hormone / Q000097:blood; D005260:Female; D005640:Follicle Stimulating Hormone / Q000097:blood*; D005498:Follicular Phase / Q000097:blood*; D006801:Humans; D007265:Inhibins / Q000097:blood; D007986:Luteinizing Hormone / Q000097:blood; D006080:Ovarian Follicle / Q000502:physiology*
chemical_list: C422364:inhibin B; D007265:Inhibins; D054304:Anti-Mullerian Hormone; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone