The sperm count of French men fell by a third between 1989 and 2005, a study suggests. The semen of more than 26,600 French men was tested in the study, reported in the journal Human Reproduction. The number of millions of spermatozoa per milliliter fell by 32.3%, a rate of about 1.9% a year. And the percentage of normally shaped sperm fell by 33.4%. The average sperm count remained within the fertile range, but experts want to see more research into possible causes. One of the paper's authors, Dr Joelle Le Moal, an environmental health epidemiologist, said: "To our knowledge, this is the first study concluding a severe and general decrease in sperm concentration and morphology at the scale of a whole country over a substantial period.

This constitutes a serious public health warning." But Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said: "The change in sperm concentration described, 73.6 to 49.9 million per milliliter [on average for a 35-year-old], is still well within the normal range and above the lower threshold of concern used by doctors which is suggestive of male infertility, 15 million per milliliter." There has much been much debate in the past 20 years over whether sperm quality has decreased, with research supporting both sides of the controversy. This latest research adds weight to the numerous European studies that suggest one in five young men has a sperm count low enough to impair fertility.

Prof Richard Sharpe, from the University of Edinburgh, said: "Something in our modern lifestyle, diet or environment like chemical exposure, is causing this. "We still do not know what the most important factors are, but perhaps the most likely is a combination, a double whammy of changes, such as a high-fat diet combined with increased environmental chemical exposures." - BBC