Metformin has gained a reputation as an effective fertility treatment in PCOS. Most publications use ovulation rate as the main outcome measure and few quote pregnancy rates. We have audited the first 39 patients with PCOS treated with Metformin in our Reproductive Unit. In this practice, as opposed to a research setting, there were often multiple factors contributing to infertility and they were usually proven resistant to other forms of treatment.
In the present study, 39 PCOS subjects (mean age, 31 yr; mean body mass index, 34.8 kilograms per metre 2) were treated with Metformin in an open trial (dose ranged from 1 to 3 grams per day; mean dose; 1.625 grams per day) for a duration of 1-24 months (median 7), to assess therapeutic rationale in view of reproductive outcomes. Eight women were amenorrhoeic, 29 were oligomenorrhoeic and 2 had normal menstrual cycles. The duration of infertility was 1-9 years (mean 3 yr); 21 had received previous fertility treatments; 17 received supplementary treatment while on Metformin (Clomiphene Citrate or hMG ).
On Metformin treatment, mean frequency of menstruation improved (p=0.001) in 29 of 39 women (77%); 12 (31%) women achieved pregnancy of whom 5 had been resistant to previous Clomiphene Citrate treatment. The outcome of pregnancies were 2 delivered, 2 miscarriages and 8 ongoing. Mean weight loss on treatment was 93.1 to 90.7 kilograms (p=0.001); mean fasting serum insulin decreased from 13.4 to9.8 microunits per millilitre (p=0.03). The fall in serum LH and testosterone concentrations did not achieve significance. Metformin treatment was well tolerated.
In conclusion, our data supports the use of Metformin for treatment of infertility in obese PCOS women who are resistant to previous fertility treatment, before proceeding to ovulation induction with gonadotropins or to IVF. Co-therapy with Clomiphene Citrate may be considered in some cases. Our results also provide a rationale for Metformin as a first line treatment in obese PCOS.
08 - 11 Apr 2002
British Endocrine Societies