Here's an interesting Cochrane Review hot off the presses, evaluating the effects of insulin-sensitizing agents on fertility.
A group of 31 studies that compared the effectiveness of these agents to a placebo were evaluated for what they said overall about the potential benefit for their use in women with PCOS who are trying to conceive. Of these, 27 were studies about metformin (likely because it is the most widely researched/used and more studies exist in the first place).
What the researchers concluded:
There is no evidence that metformin improves live birth rates whether it is used alone or in combination with clomiphene. However, metformin does improve ovulation and pregnancy rates. (Interpreted, this suggests that metformin does not help to prevent miscarriage.)
Metformin was also associated with a significantly higher incidence of gastrointestinal disturbance, but no serious adverse effects were reported. (I don't know about those of you reading this blog post who have tried metformin, but I would question the assertion that the gastrointestinal disturbance this medication causes is not a"serious adverse effect"!
IN THE WORDS OF THE AUTHORS:"In agreement with the previous review, metformin is still of benefit in improving clinical pregnancy and ovulation rates. However, there is no evidence that metformin improves live birth rates whether it is used alone or in combination with clomiphene, or when compared with clomiphene. Therefore, the use of metformin in improving reproductive outcomes in women with PCOS appears to be limited."
D-chiro-inositol was not even mentioned in the abstract, suggesting that the findings were not significant.
As with any information shared in this blog, only you and your provider can make the ultimate decision. I can tell you what went through my own mind--and heart--as I read this, was that this medication may create a lot of false hope and hurt for those who trust that it has more power than it actually does. I wouldn't wish a miscarriage on anyone.
Tang T, Lord JM, Norman RJ, Yasmin E, Balen AH. Insulin-sensitising drugs (metformin, rosiglitazone, pioglitazone, D-chiro-inositol) for women with polycystic ovary syndrome, oligo amenorrhoea and subfertility. Cochrane Database Syst Rev. 2010 Jan 20;(1):CD003053.