title: Age at hormonal onset of puberty based on luteinizing hormone, inhibin B, and body composition in preadolescent U.S. girls.
abstract: BACKGROUND
  Hormonal indicators could be useful for detecting early pubertal onset, but there is little research on how they are related to puberty in U.S. girls. We determined median age at hormonal onset of puberty based on luteinizing hormone (LH) and inhibin B (InB) and explored the extent to which body composition moderates this timing process.
  
  
  METHODS
  We analyzed anthropometric and hormone data of 698 US peri-pubertal girls ages 6-11.99 y who had participated in the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994.
  
  
  RESULTS
  Median age of hormonal onset of puberty was 10.43 y by LH and 10.08 y by InB cut-offs (1.04 mIU/ml for LH and 17.89 pg/ml for InB). Postnatal weight gain modulated onset, making it earlier by 10-11 mo among the highest (greater than +1 SD) relative to normal weight gainers. Onset occurred first in non-Hispanic black (NHB) girls, 10.08 y (95% confidence interval (CI): 10.07-10.09), followed by Mexican-American (MXAM) at 10.64 y (95% CI: 10.63-10.65), and at 10.66 y (95% CI: 10.66-10.67) for non-Hispanic white (NHW) girls using LH. With InB, onset occurred first in MXAM girls at 9.9 y, and at 10.3 y and 10.4 y for their NHB and NHW peers, respectively.
  
  
  CONCLUSIONS
  Preadolescent weight gain lowers the age at hormonal onset as defined by LH concentrations. Preventing obesity in childhood may also avert the earlier initiation of the maturation process even at the hormonal level.
authors.affiliation: Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, Georgia.
authors.forename: O Yaw
authors.initials: OY
authors.lastname: Addo
authors.affiliation: Division of Pediatric Endocrinology, University of Minnesota Amplatz Children's Hospital and Medical School, Minneapolis, Minnesota.
authors.forename: Bradley S
authors.initials: BS
authors.lastname: Miller
authors.affiliation: Department of Pediatrics, Pennsylvania State University College of Medicine, The Milton S. Hershey Medical Center, Hershey, Pennsylvania.
authors.forename: Peter A
authors.initials: PA
authors.lastname: Lee
authors.affiliation: Division of Gastroenterology, Hepatology and Nutrition, The Children's Hospital of Philadelphia, Philadelphia, Pennsylvania.
authors.forename: Mary L
authors.initials: ML
authors.lastname: Hediger
authors.affiliation: Division of Epidemiology and Community Health, University of Minnesota School of Public Health, Minneapolis, Minnesota.
authors.forename: John H
authors.initials: JH
authors.lastname: Himes
mesh_terms: D000367:Age Factors; D015415:Biomarkers / Q000097:blood; D001724:Birth Weight; D001823:Body Composition; D002648:Child; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007265:Inhibins / Q000097:blood*; D007986:Luteinizing Hormone / Q000097:blood*; D009749:Nutrition Surveys; D011627:Puberty / Q000097:blood* / Q000208:ethnology; D012737:Sex Factors; D014481:United States / Q000453:epidemiology; D015430:Weight Gain
chemical_list: D015415:Biomarkers; C422364:inhibin B; D007265:Inhibins; D007986:Luteinizing Hormone