[The effect of heavy metals on the in vitro interaction between human sperm and cervical mucus]

The sperm-cervical mucus-penetration test (SCMPT) was used in vitro to examine the influence of heavy metals (mercury, cadmium and copper) on sperm function. 30 each of freshly obtained different sperm samples with varying starting sperm motility and oestrogen-stimulated cervical mucosa from women of known fertility were used. Mercury chloride (HgCl2; 0.005-0.5 mmol/l), cadmium chloride (CdCl2; 0.05-10 mmol/l) and copper sulphate (CuSO4; 0.0001-10 mmol/l) were added to the in-vitro system. After incubation, at 37 degrees C for 6 hours, linear progression, penetration depth and motility index of the sperm (cumulative SCMPT score) were analysed. An untreated control was run in parallel with each test. The added substances, especially CdCl2 and HgCl2, significantly reduced the quantitative and qualitative penetrability of sperm (P = 0.001), in step with the concentration. The concentrations which were used, especially those of mercury, were in the range of in-vivo. measured levels. These results make clear that heavy metals can influence human sperm function.