In 11 female patients with chronic uraemia at the age of 20 to 47 years (average age: 33.1 years) the behaviour of basal and stimulated serum levels of prolactin (PRL), growth hormone (HGH) and gonadotropins (LH, FSH) was investigated. For stimulation of the hormone secretion a sequential test with arginine hydrochloride, gonadotropin releasing hormone (GnRH) and thyrotropin releasing hormone (TRH) was used. In 2 women the investigations were repeated after kidney transplantation. The determination of LH, FSH, PRL and HGH was performed radioimmunologically. The investigations show that in women with chronic uraemia the basal LH-levels in general lie clearly above of those ones of women with biphasic cycles, whereas the FSH-levels are not increased. The LH-response after administration of 25 micrograms GnRH is adequate in 6 women and is absent in 5 women. After kidney transplantation a clear reduction of the basal LH-levels in comparison to the preliminary values is to be established. The increased basal LH-levels are causally made responsible for the disturbances of the menstrual cycle in women with chronic uraemia. For PRL hyper- and normoprolactinaemic as well as hypoprolactinaemic basal levels are found. A connection between the height of the PRL and creatinine levels cannot be proved. Apart from a adequate PRL response to the stimulation with TRH in the individual case this response is inadequate or is absent. The basal HGH-levels are in the area of reference. In all women HGH can adequately be stimulated, whereby the case in question is presumably a so-called paradoxical TRH-effect.