title: Is premature thelarche in the first two  years of life transient?
abstract: OBJECTIVE
  Premature thelarche (PT) refers to isolated onset of thelarche in girls younger than 8 years of age. Most cases have an onset under 2 years of age. We aimed to establish whether the onset of thelarche under 2 years of age certifies a transient clinical course, as suggested by several authors.
  
  
  METHODS
  Sixty-seven girls with an onset of PT under 2 years of age were classified as having early puberty (EP) or classical PT after one year of follow-up. Progression of pubertal findings or absolute growth velocity (GV) standard deviation score (SDS) above 1 SDS constituted the criteria for a diagnosis of EP.
  
  
  RESULTS
  Twenty (29.1%) girls were classified as having EP and 47 (70.1%) girls as having classical PT. Basal serum luteinizing hormone (LH; ICMA) values at a cut-off level of 0.3 IU/L were found to be a significant risk factor for having an atypical course [OR=7.8; CI (95%): 2.04-30.4, p=0.003].
  
  
  CONCLUSIONS
  Onset of thelarche under 2 years of age does not assure a transient course in a remarkable proportion of girls with PT. An absolute GV value of >1 SDS or a basal LH level ≥0.3 IU/L are suggested as indicators for close follow-up.
authors.affiliation: Istanbul University, Istanbul Medical Faculty, Pediatric Endocrine Unit, Fatih, Istanbul, Turkey. aucar76@yahoo.com
authors.forename: Ahmet
authors.initials: A
authors.lastname: Uçar
authors.forename: Nurçin
authors.initials: N
authors.lastname: Saka
authors.forename: Firdevs
authors.initials: F
authors.lastname: Baş
authors.forename: Rüveyde
authors.initials: R
authors.lastname: Bundak
authors.forename: Hülya
authors.initials: H
authors.lastname: Günöz
authors.forename: Feyza
authors.initials: F
authors.lastname: Darendeliler
mesh_terms: D017668:Age of Onset; D001940:Breast / Q000473:pathology*; D002657:Child Development; D002675:Child, Preschool; D018450:Disease Progression; D012734:Disorders of Sex Development / Q000097:blood / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D004958:Estradiol / Q000097:blood; D005260:Female; D043373:Follicle Stimulating Hormone, Human / Q000097:blood; D005500:Follow-Up Studies; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000627:therapeutic use; D006801:Humans; D007223:Infant; D007986:Luteinizing Hormone / Q000097:blood; D008499:Medical Records; D011629:Puberty, Precocious / Q000097:blood / Q000453:epidemiology* / Q000473:pathology / Q000628:therapy; D012075:Remission, Spontaneous; D012189:Retrospective Studies; D012307:Risk Factors; D014421:Turkey / Q000453:epidemiology
chemical_list: D043373:Follicle Stimulating Hormone, Human; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D007986:Luteinizing Hormone