OBJECTIVETo examine and analyze semen quality and sperm ultrastructural characteristics of infertile patients with varicocele.

METHODSThis study included 118 infertile patients with varicocele (the VC group) and 76 normal semen donors (the control group). We obtained routine semen parameters, seminal plasma biochemical markers and the levels of reproductive hormones in the subjects, and observed the changes in sperm structure under the scanning electron microscope and transmission electron microscope.

RESULTSCompared with the normal control, the VC patients showed significantly decreased sperm concentration, sperm progressive motility, sperm viability (P < 0.05), but no remarkable difference in semen volume and non-progressive motility (P > 0.05). The concentrations of zinc and alpha-glycoside enzyme in the seminal plasma were markedly reduced in the VC group in comparison with the controls (P < 0.05), but there was no significant difference in the level of fructose (P > 0.05), nor in such seminal plasma biochemical markers as FSH, LH, T and E2 between the two groups (P > 0.05). The percentage of morphologically normal sperm was dramatically lower in the VC than in the control group ([56.76 +/- 15.32]% vs [12.34 +/- 6.58]%, P < 0.05), and the sperm deformities were mostly in the head and neck, mainly tapering pin head accompanied by complex abnormal differentiation.

CONCLUSIONThis study demonstrated that VC may lead to oligo-astheno-terato zoospermia, and hence male infertility, which may be attributed to the changes of seminal plasma microenvironment and sperm ultrastructure.