THE RELATIONSHIP BETWEEN FOLLICLE-STIMULATING-HORMONE DOSE AND LEVEL AND ITS RELEVANCE FOR OVULATION INDUCTION WITH ADJUVANT GONADOTROPIN-RELEASING HORMONE-AGONIST TREATMENT

Objective: To investigate the effect of a GnRH agonist (GnRH-a) on the FSH threshold level and the relationship between the FSH dose and the FSH level of patients suffering from polycystic ovarian syndrome (PCO S). Design: The stimulation with low-dose FSH in PCOS (group 1) was co mpared with the subsequently performed stimulation with low-dose FSH c ombined with GnRH-a in another group of patients suffering from the sa me syndrome (group 2). Setting: Specialist Reproductive Endocrine Unit . Patients: Suffering from clomiphene citrate-resistant PCOS. Main Out come Measures: The FSH threshold level for ongoing follicular growth a nd the relationship between dose and level of FSH. Results: In 15 pati ents in group 1 and in 13 patients in group 2, respectively, 39 and 32 stimulation cycles were performed. Below and above threshold values o f FSH of group 1 and 2 did not differ significantly. For the equation stable level of FSH (Y mIU/mL) = A x infusion rate of FSH (X IU/24 h) + basal level of FSH (B mIU/mL), the median A of group 1 was 0.027 and A of group 2 was 0.055 (significant difference). Conclusions: In PCOS , a change of the FSH threshold level for ongoing follicular growth in duced by the GnRH-a could neither be proven nor ruled out. The use of a GnRH-a resulted in larger FSH level increases per IU/24 h of FSH adm inistered and might therefore interfere with the effect of low-dose FS H treatment.