title: Luteal phase estrogen is decreased in regularly menstruating older women compared with a reference population of younger women.
abstract: OBJECTIVE
  To compare daily reproductive hormone secretion in regularly menstruating older versus younger women.
  
  
  METHODS
  This was a prospective cohort study.
  
  
  RESULTS
  Daily morning urine samples were obtained from 106 women, 28 of whom were aged between 20 and 34 years (mean: 27.8+/-3.7 y) and 78 of whom were aged between 35 and 50 years (mean: 40.3+/-3.7 y). Lower luteal estrone-3-glucuronide levels were seen in the older versus the younger group (82.7 vs 93.5 ng/ml, P=0.035). The pregnanediol-3-glucuronide levels in the older group were lower than those in the younger group throughout the entire cycle. The median length of the follicular phase was shorter in the older versus younger women (13 vs 14.5 d, P=0.005). There was no significant difference in the median luteal phase lengths between groups.
  
  
  CONCLUSIONS
  We report the new finding that regularly menstruating older women not only have lower pregnanediol-3-glucuronide levels but also have a significant reduction in luteal phase estrone-3-glucuronide compared with a contemporaneous cohort of younger women. This combined deficit may play a key role during the luteal-follicular transition, potentially affecting follicle recruitment and decreasing fecundity in the subsequent cycle.
authors.affiliation: Department of Obstetrics and Gynecology, University of North Carolina, Chapel Hill, NC, USA.
authors.forename: Jennifer E
authors.initials: JE
authors.lastname: Mersereau
authors.forename: Michele L
authors.initials: ML
authors.lastname: Evans
authors.forename: Dan H
authors.initials: DH
authors.lastname: Moore
authors.forename: James H
authors.initials: JH
authors.lastname: Liu
authors.forename: Michael A
authors.initials: MA
authors.lastname: Thomas
authors.forename: Robert W
authors.initials: RW
authors.lastname: Rebar
authors.forename: Ellen
authors.initials: E
authors.lastname: Pennington
authors.forename: Marcelle I
authors.initials: MI
authors.lastname: Cedars
mesh_terms: D000328:Adult; D000375:Aging / Q000378:metabolism*; D003430:Cross-Sectional Studies; D004970:Estrone / Q000031:analogs & derivatives / Q000378:metabolism / Q000652:urine; D005260:Female; D006801:Humans; D008183:Luteal Phase / Q000378:metabolism*; D008875:Middle Aged; D010060:Ovulation / Q000502:physiology*; D011276:Pregnanediol / Q000031:analogs & derivatives / Q000378:metabolism / Q000652:urine
chemical_list: C022270:pregnanediol-3 alpha-glucuronide; C015856:estrone-3-glucuronide; D004970:Estrone; D011276:Pregnanediol