title: Effect of light perception on menarche in blind women.
abstract: OBJECTIVE
  The role of light on human reproductive development is unclear. Women with varying degrees of visual impairment appear to have altered reproductive function compared to sighted women. These differences have been attributed in part to differences in light exposure between the sighted and the blind. The present study was conducted to determine whether differences exist in reproductive measures among blind women with at least light perception (LP) compared to women with no perception of light (NPL).
  
  
  METHODS
  We studied 1,392 (LP, n = 968; NPL, n = 417; unreported, n = 7) blind women across North America between 2005 and 2007. Statistical analysis was conducted using Student's two-sample t tests and multivariate logistic or linear regression. Models were adjusted for current age, body mass index (BMI) and BMI at age 18.
  
  
  RESULTS
  NPL women reported an earlier menarche (mean age, 12.16, standard deviation +/- 1.53) than LP women (mean age, 12.46, +/- 1.57 yrs). The adjusted odds ratio (OR) for each increasing year of menarche among NPL women compared to LP women, was 0.88 (95% confidence intervals [CI]: 0.81-0.96). When those women NPL from birth were compared to all others, the adjusted odds ratio was strengthened (OR: 0.80, 95% CI: 0.68-0.94). When we examined the association between age at onset of NPL and age at menarche, we found a significant positive association with earlier menarche being associated with an earlier age category of loss of light perception (test for trend p < 0.01).
  
  
  CONCLUSIONS
  Our findings suggest that lack of light perception affects reproductive development in women.
authors.affiliation: Division of Sleep Medicine, Brigham and Women's Hospital, Boston, Massachusetts 02115, USA. eevans@rics.bwh.harvard.edu
authors.forename: Erin E
authors.initials: EE
authors.lastname: Flynn-Evans
authors.forename: Richard G
authors.initials: RG
authors.lastname: Stevens
authors.forename: Homayoun
authors.initials: H
authors.lastname: Tabandeh
authors.forename: Eva S
authors.initials: ES
authors.lastname: Schernhammer
authors.forename: Steven W
authors.initials: SW
authors.lastname: Lockley
mesh_terms: D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D001766:Blindness / Q000503:physiopathology*; D015992:Body Mass Index; D002940:Circadian Rhythm / Q000502:physiology; D005260:Female; D006801:Humans; D008027:Light; D008572:Menarche / Q000502:physiology*; D008593:Menopause / Q000502:physiology; D008875:Middle Aged; D016017:Odds Ratio; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult