No more surrogate end-points in randomised trials: the PCOSMIC trial protocol for women with polycystic ovary syndrome using metformin for infertility with clomiphene.

Current data supporting the effectiveness of metformin as a fertility treatment for women with polycystic ovary syndrome have been misinterpreted. Still unproven for women with polycystic ovary syndrome is, first, whether metformin adds to the standard first-line fertility management in all women, second, whether metformin is an effective fertility treatment for overweight women, and third, the relative fertility efficacy of metformin and clomiphene citrate as a first-line treatment in women with a lower body weight. The PCOSMIC (polycystic ovary syndrome: metformin for infertility with clomiphene) trial is an ongoing New Zealand multicentre double-blind placebo-controlled parallel randomised trial assessing these questions.