Paradoxical pituitary hormone responses in a case of primary hypothyroidism and Hashimoto's thyroiditis.

A 24-year-old woman is described with irregular menstruation, anovulation, and infertility due to primary hypothyroidism and Hashimoto's thyroiditis. Her baseline gonadotropins and thyroid-stimulating hormone (TSH) were increased. Microsomal and thyroglobulin antibodies were present. Stimulation of pituitary hormone release with thyrotropin-releasing hormone (TRH) resulted in appropriate responses of TSH and prolactin (PRL) as well as a substantial rise in the level of luteinizing hormone (LH). Luteinizing hormone releasing factor (LRF) markedly inhibited LH release. Bromoergocryptine led to inhibition of TSH and PRL. These results suggest that specific and nonspecific responses of pituitary glycoproteins to provocative stimuli reflect a profound disturbance of the hypothalamic-pituitary axis in this case of hypothyroidism.