Effect of H2 treatment on human sperm motility in
each suspension. Seventeen sperm suspensions with a sperm
viability rate > 20% were used. Sperm motility was determined
before and after treatment with H2- or N2-mixed gases for 30 min.
Sperm motility in 12 suspensions (dark blue) improved only with H2-
mixed gas, in 4 suspensions (light blue) improved with both H2- and
N2-mixed gases and in one suspension (pink) was not activated by
both mixed gases. P-values were determined using paired t-test.