FERTILITY WRECKERS

AS MALe fertility rates decline, we look at the potential causes. This week: Not getting enough sleep DISRUPTED sleep drastically lowers young men’s fertility, research shows.

Biologists at the University of Southern Denmark found that men who often turned in late, woke many times or struggled to nod off had sperm counts that were 25 per cent lower than sound sleepers, according to the American Journal of Epidemiology.

‘The frequency of sleep disturbances has increased in the past few decades, a period in which a decline in semen quality has also been reported,’ the scientists said. Allan Pacey, a professor of andrology at Sheffield University, adds the link could be related to melatonin, the hormone that regulates sleep.

‘Studies have shown that disrupting its production can lower semen quality.’