The effects of rosiglitazone and metformin on menstrual cyclicity and hirsutism in polycystic ovary syndrome

Gynecol Endocrinol. 2005 Sep;21(3):154-60. doi: 10.1080/09513590500231627.


Objective: The aim of the present study was to assess the effects of metformin and rosiglitazone on menstrual cyclicity and hirsutism in patients with polycystic ovary syndrome (PCOS).

Materials and methods: Ninety-six patients were included in the study. Serum sex steroids, serum fasting glucose and insulin levels, and insulin response to a 75-g oral glucose tolerance test were assessed in all patients. Menstrual cyclicity, with recording of menses in the 6-month periods before the study and during treatment, was evaluated in each patient. Patients were divided into two groups: one was treated with metformin (MET group, n = 48), while the other received rosiglitazone (ROSI group, n = 48). At baseline and after 24 weeks of treatment all patients underwent hormonal and clinical assessments, including body mass index (BMI), waist and hip measurements and Ferriman - Gallwey (FG) scores.

Results: Of the 96 patients included in the study, 88 (91.7%) were able to complete it and yielded data for analyses. After the 24-week treatment period, fasting insulin levels and area under the curve for serum insulin decreased significantly, while the glucose/insulin ratio increased in both groups. The degree of reduction in serum free testosterone and androstenedione levels was similar in the two groups. The decreases in luteinizing hormone/follicle-stimulating hormone ratio and serum dehydroepiandrosterone sulfate levels were significantly greater in the ROSI group compared with the MET group. BMI increased in the ROSI group, while it decreased in the MET group. In patients with menstrual disturbance treated with rosiglitazone, menstrual cycles became regular in 87.8%, while improvement occurred in 79.3% of the patients treated with metformin. FG score decreased in both ROSI and MET groups, but the degree of decrease was significantly greater in the ROSI group than in the MET group.

Conclusion: Our data show that both metformin and rosiglitazone improve ovarian function and hirsutism in patients with PCOS. Rosiglitazone appears better than metformin in the treatment of hirsutism and has better patient tolerance.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Androstenedione / blood
  • Female
  • Glucose Tolerance Test
  • Hirsutism / blood
  • Hirsutism / complications
  • Hirsutism / drug therapy*
  • Humans
  • Hypoglycemic Agents / administration & dosage*
  • Insulin / blood
  • Menstrual Cycle
  • Metformin / administration & dosage*
  • Polycystic Ovary Syndrome / blood
  • Polycystic Ovary Syndrome / complications
  • Polycystic Ovary Syndrome / drug therapy*
  • Rosiglitazone
  • Testosterone / blood
  • Thiazolidinediones / administration & dosage*
  • Treatment Outcome


  • Hypoglycemic Agents
  • Insulin
  • Thiazolidinediones
  • Rosiglitazone
  • Testosterone
  • Androstenedione
  • Metformin