Daily blood samples were obtainedfrom 5 postmenopausal patients for 21 days and analyzed for plasma follicle stimulating hormone (FSH), luteinizing hormone (LH), esteonr, estradiol, progesterone, and serum T4. On days 8 through 14, oral thyrotropin-releasing hormone (TRH) was administeted, 50 mg, 4 times a day. All patients showed a significant T4, response. There was, however, no significant change in the plasma FSH, LH, estrone, estradiol, or progesterone. We conclude that oral administration of TRH has no influence on the elevated circulating concentration of FSH and LH seen in the postmenopausal female.