Sixty-two women with the polycystic ovarian syndrome were treated by systematic electrocautery of the ovarian capsule performed by laparoscopy. Ovulation occurred within 3 months in 92%. Regular menstrual cycles were established in 51 patients (86%) and plasma progesterone levels suggested that these were ovulatory. Seven of nine women who had been resistant to treatment with clomiphene, 150 mg daily, and human chorionic gonadotropin, 6000 to 9000 IU, ovulated after electrocauterization. The remaining two women responded to stimulation with clomiphene. Pregnancy occurred in 24 of 35 subjects who were involuntarily infertile (69%), with the pregnancy rate increasing to 80% with the inclusion of the women sensitive to clomiphene. These findings support the theory that ovulation is triggered by local factors within the ovary itself.