LDH isoenzymes in semen of infertile men.

LDH isoenzymes (LDH1, LDH2, LDH3, LDH4, LDH5, and LDHx) were evaluated in 68 infertile men and in a control of 10 fertile men. No statistically significant difference was found in the value of the 5 isoenzymes (LDH 1-5) in the different subgroups of infertile men and in the comparison of the infertile men with the control group. LDHx was detected in the infertile men, regardless of the cause of infertility, as long as the sperm concentration was greater than or equal to 16 million/ml, LDHx was not detected not only in all azoospermic men but, also, in those infertile men whose sperm count was less than or equal to 15 million/ml. There is a positive relationship (p less than 0.001) between LDHx and sperm concentration, but there is no such relationship between LDHx and % motility.