Polycystic ovary disease generally is associated with elevated androgen levels and elevated luteinizing hormone (LH) levels, whereas follicle-stimulating hormone (FSH) levels are (sub)normal. To assess the role of androgens on gonadotropin secretion, we investigated the effect of 6 weeks of testosterone (T) undecanoate, 120 to 160 mg/d orally, on the parameters of the pulsatile secretion of LH in a group of six eugonadal female-to-male transsexuals with normal menstrual cycles. The treatment suppressed menstrual activity in all patients. Serum T and estrone were significantly elevated after treatment with oral T undecanoate. The parameters of the pulsatile secretion of LH were not affected by androgen administration. Levels of FSH, estradiol, and progesterone also did not change significantly.