A double-blind, placebo-controlled comparison of letrozole to oxandrolone effects upon growth and puberty of children with constitutional delay of puberty and idiopathic short stature

Horm Res Paediatr. 2010;74(6):428-35. doi: 10.1159/000315482. Epub 2010 Jul 14.


Background/aims: Constitutional delay of growth and puberty (CDGP) with short stature is one of the most common problems in pediatrics. We compared the effects of letrozole with that of oxandrolone on predicted adult height (PAH), puberty, bone mineral density, serum insulin-like growth factor 1 (IGF-1) and blood lipoproteins.

Methods: In a prospective, double-blind, randomized, placebo-controlled clinical trial, 91 CDGP boys (12.6-14.6 years old) with predicted short stature were treated with letrozole (2.5 mg/day), oxandrolone (2.5 mg/day), or placebo, at the outpatient pediatric endocrine clinic of Mofid Children's Hospital in Tehran for 2 years.

Results: Letrozole differed from oxandrolone and placebo in significantly increasing PAH (p < 0.05), and slightly but significantly decreasing HDL-cholesterol. Oxandrolone, and to a lesser degree letrozole, significantly increased the height standard deviation score and bone age compared to placebo.

Conclusion: This first randomized controlled clinical trial in CDGD teenage boys with predicted short stature shows that letrozole increases PAH more than oxandrolone and advances pubertal stage and bone mineralization less.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Androgens / therapeutic use*
  • Aromatase Inhibitors / therapeutic use*
  • Body Height / drug effects
  • Bone Density / drug effects
  • Cholesterol / blood
  • Double-Blind Method
  • Female
  • Growth Disorders / blood
  • Growth Disorders / drug therapy*
  • Humans
  • Insulin-Like Growth Factor I / analysis
  • Letrozole
  • Male
  • Nitriles / therapeutic use*
  • Oxandrolone / therapeutic use*
  • Prospective Studies
  • Puberty, Delayed / blood
  • Puberty, Delayed / drug therapy*
  • Statistics, Nonparametric
  • Testosterone / blood
  • Triazoles / therapeutic use*
  • Triglycerides / blood


  • Androgens
  • Aromatase Inhibitors
  • Nitriles
  • Triazoles
  • Triglycerides
  • Testosterone
  • Insulin-Like Growth Factor I
  • Oxandrolone
  • Letrozole
  • Cholesterol