Purified urinary follicle stimulating hormone induces different hormone profiles compared with menotrophins, dependent upon the route of administration and endogenous luteinizing hormone activity

The effects of treatment of patients with gonadotrophin-releasinghormone analogue (GnRHa) combined with purified follicle stimulatinghormone (FSH) for in-vitro fertilization (IVF) were investigatedin detail to determine the influences of different administrationroutes and the degree of suppression of luteinizing hormone(LH). Responses to exogenous gonadotrophins were studied ininfertile women (n = 60) with normal menstrual rhythm whoseendogenous gonadotrophin activity was suppressed using a GnRHain a long protocol. They were randomized to receive i.m. administrationof human menopausal gonadotrophins (HMGim, Pergonal) or purifiedfollicle stimulating hormone (FSH, Metrodin High Purity) administeredeither i.m. (MHPim) or s.c (MHPsc). Responses were assessedby measuring plasma FSH, LH, oestradiol, testosterone and progesterone.After stimulation day 4, the MHPsc group showed significantlyhigher circulating concentrations of FSH than either the MHPimor HMGim group. However, the HMG group showed significantlyhigher oestradiol concentrations after stimulation day 5 thaneither MHP group. The differences in circulating oestradiolconcentrations in the MHP-treated patients appeared to be stronglyinfluenced by the mean circulating concentrations of LH in thefollicular phase. The patients who showed mean follicular phaseLH concentrations of <1 IU/1 showed longer follicular phases,lower circulating oestradiol and testosterone concentrationsand also lower follicular fluid concentrations of oestradioland testosterone, indicating a reduction in the normal follicularmetabolism of progesterone to androgens and oestrogens underthese conditions. This group of patients also showed longerfollicular phases, which may have consequences for future clinicalmanagement.