Between seven and a half and eight hours sleep is ideal, the study says
Men should get to bed before 10.30pm to improve their chances of fathering children, scientists have said following a groundbreaking new study.
The data showed that those tucked up early had nearly four times greater sperm quality compared to those who went to sleep at 11.30 or later.
Fertility experts said they believe a lack of sleep provokes the immune system into overreacting and attacking healthy sperm.
It also puts men under physical and psychological stress, which is thought to further damage their chances of conceiving.
The team at Aarhus University in The Netherlands said the findings are increasingly significant in the age of Netflix where people tend to binge-watch television late into the night.
They studied 104 men with an average age of 34 over a two-year period, tracking their sleep patterns and comparing them against the results of sperm sample analysis.
The figures showed that even the difference between getting to sleep before 10.30 and between 10.30 and 11.30 yielded a 2.75-times greater healthiness of sperm.
Presented at the European Society of Human Reproduction and Embryology conference in Vienna, the study contributes to a growing shift in focus towards the impact of substandard sperm in couples’ infertility, a factor scientists now believe has been underestimated for years.
Professor Hans Jakob Ingerslev, who co-authored the study, said: “The reasons could be psychological as sleep-deprived men suffer more stress and that can have an impact on fertility.
“These were men who had been trying to have a baby for about two years and an early bedtime was likely to be important because it allowed them to get more sleep.”
As well as investigating the time at which aspiring fathers went to sleep, the team also assessed sleep duration against the health of the participants’ sperm.
They found that between seven and a half and eight hours sleep was ideal.
The sperm of men who slept this length appeared to be more than six times healthier than that of those who got less than seven hours.
However, no link was found between sperm health and sleeping for eight hours or longer.
Dr Christopher Barratt, professor of reproductive medicine at the University of Dundee, said: “If you don’t get enough sleep, that has an impact on the metabolism, which will have a negative effect on sperm quality.
He added: “It is pretty basic advice but a lack of sleep is closely tied to feeling stressed and stressed men are also less likely to have sex once a day, as we recommend when trying for a baby.”
The new research follows a recent study from Imperial College London, which discovered that the sperm of infertile men is every bit as healthy as that of fertile men while it is still in the testicles.
However, by the time it has travelled through a series of ducts and left the body it has become damaged, suggesting something toxic is happening along its path to the outside.
It is thought discovery offers new hope for men who struggle to become fathers even with the help of IVF.
