Male Sperm Counts drop by a third since 1990s

Male fertility under threat as sperm counts drop within past two decades. A comprehensive study into the reproductive health of 26,600 men found sperm concentration has decreased by a third since the 1990s. The findings are so significant experts have warned action must now be taken to avoid significant fertility problems and the average family size decreasing. The study, which was carried out in France, found there had been a ''significant and continuous'' 32.2 per cent decrease in sperm concentration over 17 years. Numbers of sperm per millilitre of semen fell at about two per cent a year between 1989 and 2005, with researchers calculating the average 35-year-old man would see his sperm count reduced from around 73.6 million per millilitre of semen to 49.9 million. At the same time, the proportion of normally formed sperm declined by about a third. Writing in the journal Human Reproduction, the French authors said the study was the first to identify a long-term ''severe and general decrease'' in sperm concentration and quality at the scale of a whole country. They added: ''This constitutes a serious public health warning. The link with the environment particularly needs to be determined.'' The scientists analysed data from semen samples collected from 126 fertility clinics throughout France. All the couples involved were seeking treatment because of female problems rather than obvious difficulties linked to sperm. Dr Joelle Le Moal, one of the researchers from the Institut de Veille Sanitaire in Saint Maurice, said: ''The decline in semen concentration shown in our study means that the average values we have for 2005 fall within the 'fertile' range for men according the definition of the World Health Organisation. "However, this is just an average, and there were men in the study who fell beneath the WHO values. ''The 2005 values are lower than the 55 million per millilitre threshold, below which sperm concentration is expected to influence the time it takes to conceive.'' More promisingly, the study also showed the proportion of active or ''motile'' sperm rose slightly from 49.5 per cent to 53.6 per cent. The findings support other research showing similar drops in sperm concentration and quality in recent years. Some studies have suggested that environmental factors, such as endocrine disrupters - chemicals that upset hormone balances in the body - might be behind the trend. Dr Le Moal said: ''Impairments in the quality of human gametes (male sperm and female eggs) can be considered as critical biomarkers of effects for environmental stresses, including endocrine disrupters. Firstly, this is because gametes are the very first cells from which human beings are built up during their lifetimes. ''According to the theories about the developmental origins of health and diseases, early exposures may have an impact on adult health.'' These effects can be passed down generations by the way they impact inherited DNA, she added. A national monitoring system to assess French sperm quality is now being planned by the scientists. Professor Richard Sharpe, from the University of Edinburgh, said: ''The take-home message from the study is extremely simple - sperm number and sperm quality has declined progressively over the study period. ''In the UK this issue has never been viewed as any sort of health priority, perhaps because of doubts as to whether 'falling sperm counts' was real. Now, there can be little doubt that it is real, so it is a time for action. "Doing nothing will ensure that couple fertility and average family size will decline below even its present low level and place ever greater strains on society.'' Article: 6th December 2012 www.telegraph.co.uk

Wearing tight Y-fronts really does affect sperm counts

UK study has shown that men with unhealthy lifestyles produce as much swimming sperm as those living more sensibly. But those who wore tight underwear instead of loose boxer shorts and did manual work had lower sperm counts. Under current guidelines, GPs are supposed to warn men diagnosed with infertility of the dangers of alcohol, tobacco and recreational drugs. Infertile men are also urged to avoid being overweight. In some cases, fertility treatment is delayed to allow couples time to improve their lifestyles. But the new research suggests none of these factors has much impact on the number of swimming sperm a man produces. Co-author Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said men should still take care of themselves, without feeling the need to ''become monks''. '''In spite of our results, it's important that men continue to follow sensible health advice and watch their weight, stop smoking and drink alcohol within sensible limits. But there is no need for them to become monks just because they want to be a dad. "Although if they are a fan of tight Y-fronts, then switching underpants to something a bit looser for a few months might be a good idea.'' Scientists recruited 2,249 men from 14 fertility clinics around the UK and asked them to fill out detailed lifestyle questionnaires. Information was then compared from 939 men who produced low numbers of swimming sperm and 1,310 men who produced higher numbers. The results, reported in the journal Human Reproduction, showed that men with poor quality sperm were 2.5 times more likely to have had testicular surgery, and twice as likely to be of black ethnicity. They were also 1.3 times more likely to do manual work, not wear loose boxer shorts, or not to have had a previous conception. But men's use of tobacco, alcohol and recreational drugs made little difference, as did their weight as measured by body mass index (BMI). Study leader Dr Andrew Povey, from the University of Manchester, said: ''Despite lifestyle choices being important for other aspects of our health, our results suggest that many lifestyle choices probably have little influence on how many swimming sperm they ejaculate. For example, whether the man was a current smoker or not was of little importance. The proportion of men who had low numbers of swimming sperm was similar whether they had never been a smoker or a smoker who was currently smoking more than 20 cigarettes a day. ''Similarly, there was little evidence of any risk associated with alcohol consumption. ''This potentially overturns much of the current advice given to men about how they might improve their fertility and suggests that many common lifestyle risks may not be as important as we previously thought. ''Delaying fertility treatment then for these couples so that they can make changes to their lifestyles, for which there is little evidence of effectiveness, is unlikely to improve their chances of a conception and, indeed, might be prejudicial for couples with little time left to lose.'' The number of swimming sperm broadly correlates with how fertile a man is likely to be. It also often determines the type of fertility treatment that is offered. Fellow expert Professor Nicola Cherry, formerly at the University of Manchester and now with the University of Alberta in Canada, added: ''The higher risk we found in manual workers is consistent with earlier findings that chemicals at work could affect sperm and that men should continue to keep work exposures as low as possible.'' Article: 13th June 2012 www.telegraph.co.uk