Effect of clomiphene citrate on sperm cell function.

Experiments were performed to determine time and dose-dependent effects of clomiphene citrate on the function of fertile donor spermatozoa. The percentages of acrosome-reacted, motile and live spermatozoa were assessed. Incubation with clomiphene citrate (1-1000 mumol/l; 1-4 h) induced a dose- and time-dependent increase in the percentage of acrosome-reacted spermatozoa (up to 100%). Acrosome reaction was associated with an impairment of both motility and viability. The maximal value for percentage of live reacted spermatozoa (37 +/- 1%) was obtained when cells were incubated for 1 h with 100 mumol/l of clomiphene citrate. Oestradiol neither affected sperm function when used alone nor inhibited clomiphene action. These results show that clomiphene strongly triggers the acrosome reaction, but that this action is not related to its anti-oestrogenic properties.