RESEARCHERS from Queen's University have shown that excess sugar in the blood directly affects sperm quality and consequently male fertility, overturning popular perceptions.

The increasing number of youths being diagnosed with diabetes has coincided with global concerns over male fertility, pointed out Con Mallidis of Queen's in Belfast, who led the research. "But this is not simply a coincidence.

We have shown for the first time that diabetes adversely influences male fertility at a molecular level," he added.

Scientists studied semen samples from diabetic men receiving insulin therapy. On routine microscopic examination, the semen samples appeared normal, except for slight decrease in volume.

"But when we looked for DNA damage, we saw a very different picture," said Mallidis, adding that this is not part of a routine semen analysis.

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