The optimum dose and mode of administration of luteinizing hormone releasing hormone analogue in in-vitro fertilization: a comparison of three regimens.

Three regimens for administration of the luteinizing hormone releasing hormone analogue (LHRHa), buserelin, were compared in terms of pituitary down-regulation prior to ovarian stimulation for in-vitro fertilization (IVF). Thirty-three patients who had failed to conceive in previous IVF cycles were randomly divided into three groups. Patients in Group I (n = 11) received intranasal (i.n.) buserelin 200 micrograms four hourly for 21 days; patients in Group II (n = 11) received subcutaneous (s.c.) buserelin 500 micrograms twice a day for 7 days, followed by 500 micrograms daily for 14 days; patients in group III (n = 11) received (s.c.) buserelin 500 micrograms three times a day for 7 days. In all three groups administration of buserelin was continued until serum oestradiol levels were less than 100 pmol/l, at which time human menopausal gonadotrophin (HMG) was commenced. All the patients achieved pituitary down-regulation after seven days of treatment with buserelin, except for four patients who developed ovarian cysts and two with polycystic ovarian disease. The total dose of HMG used and the ongoing pregnancy rate were not significantly different between the three groups. A much higher proportion of patients in Group I developed side-effects and found their treatment disruptive to their life-style. Our results suggest that patient variables (e.g. polycystic ovaries, ovarian cysts) rather than the dose and mode of administration of buserelin, are the major determinant of the length of time needed for pituitary down-regulation. The s.c. route is preferable and the smallest dose of buserelin that will produce pituitary down-regulation should be used.