CANNABIS 'DAMAGES MALE FERTILITY'

Cannabis was reclassified as a class C drug in January

Men who smoke cannabis could be damaging their fertility, research carried
out by Queen's University Belfast has suggested.

The study by the university's Reproductive Medicine Research Group examined
the direct effects on sperm function of THC, the active ingredient in cannabis.

The group found that THC made sperm less likely to reach the egg to
fertilise it.

They also discovered that the presence of cannabis impaired another crucial
function of sperm - the ability to digest the egg's protective coat with
enzymes to aid its penetration.

The government reclassified cannabis to a class C drug in January, putting
it on a par with tranquilisers.

'Informed choice'

Dr Sheena Lewis, from the university's Department of Obstetrics and
Gynaecology, said on Wednesday that the recent reclassification of cannabis
made research on its effects more important.

"The need to determine its effects on male fertility is even greater, so
that men can make an informed choice about smoking the drug based on its
risks to their health," she said.

The idea for the study came after researchers looking at the lifestyle
habits of infertile men noticed that many men attending infertility clinics
at Belfast's Royal Maternity Hospital were regular cannabis users.

Dr Lewis told delegates at the British Fertility Society's annual meeting
in Cheltenham that recent experiments on sea urchin sperm suggested that
cannabis may be a major cause of infertility.

"These experiments on human sperm tell the same story," she said.

One in six couples in the UK are affected by infertility, with 40% of these
cases due to problems with sperm.

Dr Lewis said: "It is estimated that 3.2m people in Britain smoke cannabis,
and that figure may now increase.

"Add the two together and we may find that the use of recreational drugs
will exacerbate male fertility problems."