Pregnant smokers risk sons' fertility

Men whose mothers smoked during pregnancy are significantly more likely to suffer from fertility problems, it emerged today.

New research has revealed that boys exposed to tobacco in the womb have a dramatically reduced sperm count when they grow up.

Their sperm is also likely to be significantly weaker - giving it less chance of creating a pregnancy.

Experts now believe smoking during pregnancy has serious long-term implications for the reproductive health of children - and urged mothers to quit.

The new study involving almost 2000 young men from five European countries emerged as a second, British-based study, showed a drop of almost 30 per cent in average sperm concentrations in just 13 years. The British study, which involved more than 7,500 men, showed that average sperm count fell from nearly 87 million sperm per millilitre measure to just above 62 million.

Researchers based at the University of Southern Denmark have now discovered evidence of a strong link between a reduction in the quality of sperm and maternal smoking.

The results revealed that men whose mothers smoked during pregnancy had a 25 per cent poorer sperm count than those whose mothers did not smoke. Their sperm was also less likely to be "motile" - meaning it cannot move as fast or effectively - and the men were likely to have smaller testes.

The report, published in the American Journal of Epidemiology, concludes: "Maternal smoking may have long-term implications for the reproductive health of the offspring. This is another good reason to advise pregnant women to give up smoking."

Thousands of women in Britain still smoke during pregnancy, despite massive efforts by GPs to persuade them to quit. Statistics published last month showed that in some areas, up to a quarter of pregnant women continue to smoke, despite being told they are risking their baby's life.

The habit is known to be linked to premature birth, lower birth weight and cot death. Celebrity smokers such as model Liz Hurley, and former Radio DJ Zoe Ball, both of whom gave birth to sons, stopped smoking as soon as they became pregnant.