Endocrine Abstracts

Background: Metformin is increasingly used in the management of polycystic ovary syndrome (PCOS) but there remain differences in opinion as to its precise role in terms of clinical benefit. We retrospectively reviewed the effects of metformin on menstrual regularity, fertility, weight and hirsutism in 244 patients with PCOS treated routinely with metformin in our clinics.

Results: Patients were of median age 27 years (range 12–47) with median BMI of 35.1 kg/m² (range 20.5–61.4). BMI was <25 in 6%, 25–30 in 15%, 30–40 in 51% and >40 in 28%. Menstruation was restored in 52% of patients presenting with amenorrhoea (17/33) and in 60% of patients with oligomenorrhoea (102/170). Pregnancy was achieved in 39% of patients with a recorded diagnosis of primary or secondary infertility (28/72). Four of these experienced miscarriage. In patients who had taken metformin for at least 6 months, 49% (87/177) lost greater than 2 kg in weight. Clinically significant improvement in hirsutism was documented in only 14% (17/123). Type 2 diabetes had been diagnosed in 15 patients before or at the time of starting metformin, but was subsequently diagnosed in a further 5 patients.

Conclusion: Our findings from routine clinical practice support the efficacy of metformin in the treatment of menstrual disturbance and infertility in women with PCOS. We found weight reduction in a significant minority but limited efficacy in the treatment of hirsutism. As expected, Type 2 Diabetes is relatively common in this population, and a systematic approach to documentation of glucose tolerance is appropriate. Since this is a retrospective, non-randomised study we cannot assess the extent to which dietary, exercise or lifestyle improvements contributed to the response to metformin. Further prospective clinical studies are required to clearly define the role of metformin in clinical practice in PCOS.