Preliminary studies initially suggest that hyperinsulinemia contributes to the anovulation of the clomiphene resistant patient and to anovulation in general. Measures to reduce serum insulin such as metformin, could be used as adjunctive therapy with clomiphene to induce ovulation in women resistant to clomiphene alone. Results would also show which patients would benefit from metformin. In addition, the possibility is raised that these measures could reduce the dosage of clomiphene used, increase the number of anovulatory patients requiring gonadotropin injections with associated high cost, inconvenience, and increased multiple gestation and ovarian hyperstimulation tests.