Sequential use of clomiphene citrate, human menopausal gonadotropin, and human chorionic gonadotropin in human in vitro fertilization. I. Follicular growth and oocyte suitability.

Sequential treatment with clomiphene citrate, human menopausal gonadotropin, and human chorionic gonadotropin was successfully applied to 149 women in the framework of an in vitro fertilization and embryo transfer program and led to the birth of normal children. An average of 3.5 follicles was promoted at each cycle. Oocyte maturity was evaluated at recovery either histologically or with respect to cumulus-oocyte complexes (COC) and correlated to oocyte fertilizability. Three types of COC are described according to cell dissociation and mucification. The most expanded cumulus mass (type I) was highly fertilizable, compared with granular and poorly dissociated cumulus complexes (types II and III, respectively). No improvement in the type II and III oocyte fertilizability was obtained when type I follicular fluid was added to the incubation medium. Moreover, incubation of type III oocytes in medium containing type III follicular fluid seemed to decrease their fertilizability.