Smoking marijuana causes fertility problems because it makes men’s sperm ‘lazily swim in circles’ say experts

Men who smoke too much marijuana could face fertility problems because the drug makes sperm ‘mellow’ causing it to ‘swim in circles’.

Cannabis – which is the most widely-used illegal drug in Britain – tends to leave users feeling chilled out and relaxed.

But now researchers have revealed that it has the same effect on sperm and regular weed smoking can cut counts of the cells by as much as a third.

Dr Victor Chow, of the University of British Columbia in Canada, said: ‘The weight of the ­evidence is that marijuana ­probably has a negative impact not only for sperm counts but sperm function.’

Researchers have revealed that cannabis has a relaxing effect on sperm leaving it ‘mellow’ and potentially cutting counts of the cells by a third

Previous studies have shown that marijuana can affect fertility by cutting sperm count and suppressing ovulation in women.

The exact way in which that happens has not yet been made clear but the new research appears to shed more light.