Randomized controlled trial evaluating response to metformin versus standard therapy in the treatment of adolescents with polycystic ovary syndrome

J Pediatr Endocrinol Metab. 2005 Aug;18(8):761-8. doi: 10.1515/jpem.2005.18.8.761.


Objective: We evaluated the hypothesis that metformin would improve signs and symptoms of polycystic ovary syndrome (PCOS) in adolescents as compared to oral contraceptive pills (OCP) and have a favorable effect on obesity.

Study design: Thirty-five obese, post-menarchal, non-sexually active adolescents aged 12-21 years with PCOS and hyperinsulinism were randomly assigned to receive either OCP or metformin for 6 months.

Results: There was a significant decrease in BMI in the two groups over time, from 40.1 to 38.6 in the OCP group, and 37.3 to 36.3 in the metformin group, p = 0.0026, but no significant difference in the degree of change between the two groups. Both groups had decreased free testosterone (OCP: 1.8 pg/ml to 0.96 pg/ml; metformin: 2.1 pg/ml to 1.6 pg/ml), p < 0.0001, and improvements in insulin resistance as evidenced by increased glucose/insulin (G/I) ratio (p < 0.005) and increased QUICK1 scores (p < 0.0005). No significant differences in response to treatment were found between the metformin and OCP groups in outcome variables.

Conclusion: Adolescents with PCOS treated with metformin or OCP experienced similar beneficial outcomes including reduction in androgen levels, weight loss, and increased insulin sensitivity. The choice of a treatment agent for long-term use will depend on safety profiles, therapeutic goals and patient adherence.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adolescent
  • Adult
  • Androgens / blood
  • Child
  • Contraceptives, Oral / therapeutic use*
  • Female
  • Humans
  • Hyperinsulinism
  • Hypoglycemic Agents / therapeutic use*
  • Insulin Resistance
  • Metformin / therapeutic use*
  • Obesity
  • Polycystic Ovary Syndrome / drug therapy*
  • Treatment Outcome
  • Weight Loss


  • Androgens
  • Contraceptives, Oral
  • Hypoglycemic Agents
  • Metformin