The inhibitory effect of anticonvulsants on human sperm motility: Measured with a trans-membrane migration method

The in-vitro effects of four anticonvulsant drugs (phenytoin, phenobarbitone, carbamazepine and valproate) on human sperm motility were studied with a trans-membrane migration method. Sperm motility was measured either immediately after semen had been mixed with the drug or after a 2-hour pre-incubation at 37°C. When the drug effect was evaluated after the semen-drug mixture had been pre-incubated for 2 hours, the concentration of phenytoin, carbamazepine and valproate that inhibited sperm motility to 50% of control (EC₅₀) was 1.59, 4.23, and 5.00 mM, respectively. If sperm motility was immediately measured without preincubation, the EC₅₀ was increased to 8.47 and 100.00 mM for carbamazepine and valproate, respectively, whereas phenytoin could not inhibit sperm motility to less than 50% of the control at the tested concentrations. Both with and without pre-incubation, phenobarbitone, even up to 12.92 mM, could not inhibit sperm motility to less than 50% of the control. The result was compatible with previous findings that drugs with a membrane stabilizing effect may inhibit human sperm motility. This study provided further information regarding the application of human sperm motility as a cellular model for future pharmacological research.