Page URL:

Danish study suggests fertility fall-off for sleep-deprived men

29 April 2013
Appeared in BioNews 702

A study conducted by the University of Southern Denmark has found evidence that suggests men who do not get enough sleep are likely to be less fertile. Many studies have been conducted to discover the link between sleep and healthy living, but this was the first to look specifically for a link between sleep and male fecundity.

The study was conducted by taking sperm samples from 953 Danish men in their late teens to early twenties and asking them to fill out a questionnaire on sleeping patterns. The researchers found that men who suffered from disturbed sleep patterns or got less than 6 hours sleep a night saw a reduction in sperm concentration by over a quarter and also had smaller testicles.

Sleep disturbance was determined by asking the men if they had difficulty falling asleep, how often they woke up during the night and how much time it then took them to get back to sleep. The answers were then scored and compared to the corresponding semen sample and there appeared to be a correlation between low-scoring low-sleep individuals and sperm concentration, sperm count, motility and quality.

Dr Tina Kold Jensen, the lead researcher, hopes the next avenue of research will be to find out whether stabilising the sleeping pattern or making sure males get the recommended seven to eight hours of sleep will reverse the effect and bring sperm levels back up to normal.

In a commentary on the Danish paper, Dr Rémy Slama from Joseph Fourier University in France, went on to say that there are many factors that affect sperm production, such as tobacco smoke, obesity, exposure to heavy metals and atmospheric pollutants.

Individually, these factors only add a small amount of stress to the sperm production mechanisms, but may accumulate to produce a complex series of interacting variables. The researchers in the Danish study pointed out that men who get less sleep tend to have unhealthier lifestyles and drink more alcohol, are more overweight or are more likely to be smokers.

They also explained that the production of testosterone may be affected by sleeping with lower levels of the hormone associated with poor sleeping patterns.

Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield, said it was unlikely that poor sleep would have a major impact on fertility, however.

A lack of sleep can reduce a man's sperm count by a THIRD
Mail Online |  25 April 2013
Association of Sleep Disturbances With Reduced Semen Quality: A Cross-sectional Study Among 953 Healthy Young Danish Men
American Journal of Epidemiology |  7 April 2013
Invited Commentary: Sleep Disturbances - Another Threat to Male Fecundity?
American Journal of Epidemiology |  7 April 2013
Sleep loss can damage male fertility
Daily Telegraph |  25 April 2013
22 October 2018 - by Dr Katie Howe 
Men produce the higher quality sperm in autumn and spring, according to a large study in the USA...
31 March 2014 - by Dr Katie Howe 
A US study suggests that preconception stress is associated with lower levels of fertility in women attempting to conceive naturally. However, the study has several limitations and experts warn that worrying about the role of stress in fertility may in fact lower chances of conceiving....
11 November 2013 - by Dr Rachel Montgomery 
High levels of air pollution are to blame for a distinct drop in semen quality in Shanghai, according to the doctor who runs the city's main sperm bank...
4 November 2013 - by Dr Naqash Raja 
A fertility test which allows men to check their sperm count in the comfort of their home - or wherever they feel is most suitable - has gone on sale in the UK...
18 March 2013 - by Simon Hazelwood-Smith 
Human semen quality may rise and fall in seasonal variation, with the best quality being produced in the winter and spring...
4 March 2013 - by Dr Shanya Sivakumaran 
Inadequate sleep alters the activity of over 700 genes, scientists report. In the research, sleeping less than six hours per night for just one week impacted genes related to metabolism, inflammation and immunity...
11 February 2013 - by Dr Linda Wijlaars 
Physical activity is strongly associated with men's sperm quality according to a study looking into the effects of TV viewing and exercise...
10 December 2012 - by James Brooks 
Between 1989 and 2005, the sperm count of French men dropped by a third, according to research...
to add a Comment.

By posting a comment you agree to abide by the BioNews terms and conditions

Syndicate this story - click here to enquire about using this story.