Pituitary-ovarian function was studied in 2 women with congenital absence of the uterus and the vagina. Daily scrum levels of luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin, estradiol-17β and progesterone were measured by radioimmunoassay for 1 month. Gonadotropins and ovarian steroids showed normal cyclic variations in both patients. Prolactin was persistently elevated in one of them, who also demonstrated 2 abnormally high testosterone values among 6 determinations. The pituitary gland was stimulated by intravenous administration of lutenizing hormone and thyrotropin-releasing hormone (LRH-TRH). Gonadotropin and prolactin responses to LRH-TRH were normal. The lifelong absence of the uterus does not alter the function of the pituitary-ovarian axis. The relation of hyperprolactinemia to this syndrome must be ascertained in a greater number of patients.