[Gonadotropin stimulation during LH/RH analog-induced inhibition of pituitary function].

Ovarian stimulation with hMG/hCG is most effective in hypogonadotropic patients. In normogonadotropic/estrogen-positive patients in whom gonadotropin therapy is also indicated after failure of other forms of treatment, it is much more difficult and considerably less effective. The objective of this study was to change the endocrine status in patients from a normogonadotropic and estrogen-positive status, by administration of a GNRH analogue, to a hypogonadotropic, estrogen-negative status, in order to create better conditions for gonadotropin stimulation. For this purpose Buserilin was administered either intranasally or intravenously and the endocrine reaction was observed. The endocrine changes observed were very varied. In the majority of cycles a fall in plasma FSH concentrations resulted (20 out of 28), in 2 a rise, while in 6 of the 28 there was no change. In 12 out of 28 cycles the plasma LH concentration decreased; it rose in 3 and was unchanged in 13. The LH fluctuation was suppressed or irregular in all cases. Estrogen secretion was unaffected in 16 cycles; it increased continuously in 6 cycles and temporarily in a further 6. The reaction to the hMG injections did not show the hoped-for improvement with simultaneous administration of an RH analogue. A complete and constant suppression of pituitary function, and thus the creation of a hypogonadotropic state, could not be achieved by medication with 8 X 300 micrograms Buserilin or intravenous injection of 5 and 10 micrograms every 90 minutes.