title: Earlier menarcheal age in Spanish girls is related with an increase in body mass index between pre-pubertal school age and adolescence.
abstract: BACKGROUND
  Higher body mass index (BMI) has been associated with earlier pubertal development.
  
  
  OBJECTIVE
  The aim of this longitudinal study was to determine menarcheal age in a Spanish cohort and to assess its association with anthropometric variables at birth, childhood and adolescence. We also analyse whether the tracking of weight between different ages could affect the timing of menarche.
  
  
  METHODS
  The sample population included 195 randomly selected 6-8-year-old girls who participated in the baseline of the Four Provinces Study and in the follow-up of this study at 13-16 years old. Anthropometrical variables were measured and BMI and BMI z-score were calculated. Information regarding birth weight and menarche was obtained by means of self-report questionnaire.
  
  
  RESULTS
  Correlation analysis showed a significant negative association of age at menarche with weight, BMI and BMI z-score in the baseline and follow-up groups but not with weight at birth. Fat mass at adolescence is related to a significantly earlier menarcheal age. When comparing weight categories, earliest menarcheal age is associated with an increase of BMI between 6-8-year-old and 13-16-year-old girls.
  
  
  CONCLUSIONS
  In our study, high weight in girls is associated with the earliest age at menarche. This becomes a major influence when weight gain occurs between pre-pubertal school age and adolescence.
authors: Lipid Research Laboratory, IIS-Fundacion Jimenez Díaz, Madrid, Spain.|Department of Pediatrics, IIS-Fundacion Jimenez Díaz, Madrid, Spain.
authors: T
authors: T
authors: Gavela-Pérez
authors: Lipid Research Laboratory, IIS-Fundacion Jimenez Díaz, Madrid, Spain.
authors: C
authors: C
authors: Garcés
authors: Lipid Research Laboratory, IIS-Fundacion Jimenez Díaz, Madrid, Spain.
authors: P
authors: P
authors: Navarro-Sánchez
authors: Department of Pediatrics, IIS-Fundacion Jimenez Díaz, Madrid, Spain.
authors: L
authors: L
authors: López Villanueva
authors: Lipid Research Laboratory, IIS-Fundacion Jimenez Díaz, Madrid, Spain.|Department of Pediatrics, IIS-Fundacion Jimenez Díaz, Madrid, Spain.
authors: L
authors: L
authors: Soriano-Guillén
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000886:Anthropometry; D015992:Body Mass Index; D001835:Body Weight; D002648:Child; D005260:Female; D006801:Humans; D008137:Longitudinal Studies; D008572:Menarche / Q000502:physiology; D050177:Overweight / Q000453:epidemiology*; D011627:Puberty; D012574:Schools; D057566:Self Report; D013030:Spain / Q000453:epidemiology
keywords: Body mass index; menarcheal age; tracking