Regular sexual activity can increase men’s fertility. A study suggests that storage – both inside and outside the body – affects the quality of sperm.

Conversely, regular ejaculation could increase the prospect of having children in men who want to have children, writes a British-German research team in the “Proceedings of the Royal Society B“.

So far, abstinence is recommended

The World Health Organization advises men who have an unfulfilled desire to have children (WHO) before making sperm donations, for example for artificial insemination, two to seven days of sexual abstinence. The research team led by biologist Krish Sanghvi from the University of Oxford now firmly contradicts this. The group had previously evaluated 115 studies with a total of almost 55,000 men as well as 56 studies on representatives of other species.

Sperm quality suffers over time

So she suffers Quality of sperm with the time of their storage. The researchers explain this with the so-called post-meiotic sperm senescence (PMSS), i.e. the aging of the sperm after they are formed. This was included in the studies

• increasing damage to the genetic material,
• with oxidative stress,
• reduced mobility
• and reduced functionality.

Conclusion: Ejaculate more regularly

“Because sperm are highly mobile and have little cell plasma, they use up their stored energy reserves very quickly and have limited repair capacity,” explained co-author Rebecca Dean. “This makes storage particularly damaging compared to other cell types.” Regular ejaculation can increase men’s fertility.

The researchers complain that this is not taken into enough account in reproductive medicine. “Ejaculates should be viewed as populations of individual sperm that undergo birth, death, aging and dying,” said lead author Sanghvi. The WHO’s abstinence period of up to seven days before sperm donation is too long.

Not the first study to show this

This corresponds to the results of a Chinese study with a good 450 couples who underwent artificial insemination.

• The men had an ejaculation abstinence of maximum 48 hoursthe chance of pregnancy was a good 54 percent.
• There was abstinence two to seven dayson the other hand it was only just under 45 percent, as the Chinese team said in an unreviewed preprint at “SSRN” (Preprint server of the specialist journal “The Lancet”) writes.

Females as better sperm carriers?

Curiously, the current study by Sanghvi’s team also shows that in some other species, sperm are much better stored in the bodies of female animals than in males. This is the case, for example, with some bats, where the female animals store sperm for months during their hibernation period after mating. For some reptiles, such storage could even take years. Here, females have special organs that not only store the sperm, but also supply them with antioxidants and thus maintain their quality.

The findings on sperm quality could not only be used in fertility clinics and artificial insemination, but also in breeding programs for endangered species in zoos, writes Sanghvi’s team.