Ten lots of dissociated hMG were characterized by reverse-phase gradient high-performance liquid chromatography. Areas of 12 discrete peaks were directly related to dosages of hMG injected. The lots were further analysed for immunoactive-FSH (41.6-106.2 IU/ampule), immunoactive-LH (11.0-20.4 IU/ampule), bioactive-LH (2.7-17.1 IU/ampule) and bioactive-hMG (149-298 pg E2/mIU immunoactive-FSH/ml). Relationships between integrated areas of the HPLC peaks and biochemical properties of the hMG lots were analysed by stepwise multiple linear regression. Between-lot differences in immunoactive-LH and immunoactive-FSH were related to HPLC peak areas (p<0.05); differences in bioactive-LH were not. Areas of 8 peaks were related to differences in bioactive-hMG activity, facilitating close approximation of bioactive-hMG from the derived multi-linear model (p<0.001). Rapid characterization of hMG by HPLC is of relevance as recent reports have shown that ovarian responses and pregnancy outcomes of patients are related to the immunoactive and bioactive gonadotropin content of hMG preparations used to induce multiple folliculogenesis before oocyte aspiration, in vitro fertilization, and embryo replacement.Exogenous gonadotropins currently used to en¬ hance, or replace, endogenous gonadotropin se¬ cretion in humans are derived from the urine of post-menopausal women. The composition of dif¬ ferent lots of urinary substrate is variable, gonado¬ tropin content being markedly influenced by the age and endocrine status of the urine donors (1,2). The gonadotropins derived from human urine are also heterogeneous, there being at least 11 isoforms of hFSH (3) and about 7 hLH isoforms (4,5). Anal¬ yses of differences in biologic and biochemical characteristics of hMG (6) and differences in ova¬ rian responses and pregnancy outcomes of groups of patients treated with different hMG prepara¬ tions (7,8) have led to identification of those prop¬ erties of hMG which relate to patient response (9). However, as the methods used to establish the clin¬ ically significant properties of hMG are time-con¬ suming and expensive, they cannot be routinely applied to identify which hMG preparation(s) might be most effective in a particular patient treat¬ ment regimen. Furthermore, these screening tech¬ niques cannot identify which chemical properties of hMG preparations relate to biopotency. In these respects, we have analysed different lots of hMG by reverse-phase high-performance liquid chromatography (HPLC). Elements of the HPLC chromatograms are then correlated with the biologic and biochemical properties of hMG which have been associated with clinical efficacy.
Materials and Methods hMG preparationsTen lots of injectable hMG (Pergonal, Laboratoires Serono SA, Aubonne, Switzerland) were analysed. The lot numbers were 03365088, Immunoactive FSH. Levels of immunoactive FSH in am¬ pules were determined using an immunoradiometric sandwich assay (MAIAclone, Serono Diagnostics, Norwell, MA), sensitive to 0.025 mlU FSH/tube. The lyophilized contents of single ...