Eight infertile hyperandrogenic and oligomenorrheic women were investigated for lowering serum testosterone levels and inducing regular ovulation by Shakuyaku-Kanzo-To (mixed extracts of Paeonae Radix and Glycyrrhizae Radix). Serum testosterone levels (50-160 ng/dl) were lowered to less than 50 ng/dl in 7 patients by Shakuyaku-Kanzo-To 5-10 g daily administered for 2-8 weeks. Six of 7 patients ovulated regularly and 2 of 6 patients conceived. Serum LH levels, which were shown to be above 30 mIU/ml in 7 patients were lowered to less than 30 mIU/ml in 5 patients by dexamethasone 1 mg daily administered for 6.5 days. All of these patients ovulated regularly by Shakuyaku-Kanzo-To. No side effects were observed. Thus, Shakuyaku-Kanzo-To is indicated for lowering serum testosterone levels and inducing regular ovulation and pregnancy in infertile hyperandrogenic patients, especially in the patients whose serum LH levels were shown to be lowered to less than 30 mIU/ml by dexamethasone.