title: Childhood hair product use and earlier age at menarche in a racially diverse study population: a pilot study.
abstract: OBJECTIVE
  Previous studies suggest that hair products containing endocrine disrupting chemicals could alter puberty. We evaluated the association between childhood hair product use and age at menarche in a racially diverse study population.
  
  
  METHODS
  We recruited 300 African-American, African-Caribbean, Hispanic, and white women from the New York City metropolitan area who were between 18-77 years of age. Data were collected retrospectively on hair oil, lotion, leave-in conditioner, perm, and other types of hair products used before age 13. Recalled age at menarche ranged from 8 to 19 years. We used multivariable binomial regression to evaluate the association between hair product use and age at menarche (<12 vs. ≥12), adjusting for potential confounders.
  
  
  RESULTS
  African-Americans were more likely to use hair products and reached menarche earlier than other racial/ethnic groups. Women reporting childhood hair oil use had a risk ratio of 1.4 (95% confidence interval [CI]: 1.1-1.9) for earlier menarche, adjusting for race/ethnicity and year of birth. Hair perm users had an increased risk for earlier menarche (adjusted risk ratio = 1.4, 95% CI: 1.1-1.8). Other types of hair products assessed in this study were not associated with earlier menarche.
  
  
  CONCLUSIONS
  Childhood hair oil and perm use were associated with earlier menarche. If replicated, these results suggest that hair product use may be important to measure in evaluating earlier age at menarche.
authors.affiliation: Connors Center for Women's Health and Gender Biology, Brigham and Women's Hospital, Boston, MA 02120, USA.
authors.forename: Tamarra
authors.initials: T
authors.lastname: James-Todd
authors.forename: Mary Beth
authors.initials: MB
authors.lastname: Terry
authors.forename: Janet
authors.initials: J
authors.lastname: Rich-Edwards
authors.forename: Andrea
authors.initials: A
authors.lastname: Deierlein
authors.forename: Ruby
authors.initials: R
authors.lastname: Senie
mesh_terms: D000293:Adolescent; D000328:Adult; D001741:Black or African American / Q000706:statistics & numerical data*; D017668:Age of Onset; D000368:Aged; D002648:Child; D005260:Female; D006203:Hair Preparations; D006801:Humans; D007407:Interviews as Topic; D008572:Menarche / Q000208:ethnology; D008875:Middle Aged; D009519:New York City; D010865:Pilot Projects; D014505:Urban Population; D055815:Young Adult
chemical_list: D006203:Hair Preparations