Want to improve your sperm quality? Try casual sex with a new partner once in a while and ramp up the sperm count, an interesting study has revealed.

Men produced higher quality ejaculates when exposed to novel, rather than familiar women, the researchers found.

“Additionally, men ejaculated more quickly when viewing a new woman after being exposed to the same woman repeatedly,” added the team from the College of Wooster in Ohio.

For the study published in the Journal of Evolutionary Psychological Science, the team asked 21 men to provide semen samples while watching seven different explicit three-minute clips of a male and female having sex.

The participants used the same private room to produce the semen with 48 to 72-hour breaks between each session, The telegraph reported.

The first six clips used the same male and female actor while the seventh clip used the same male actor but involved a different female.

Apart from the quality of sperm produced, the length of time it took to ejaculate was also recorded.

The researchers found that the men produced healthier, higher volume sperm in a shorter amount of time when exposed to the seventh clip featuring a different looking female.

“An increase in the total number of motile sperm may result in higher likelihood of fertilisation and greater ability to compete with other male’s sperm,” they wrote.

Whereas a decrease in the time to ejaculation may decrease the likelihood of an extra-pair copulation (with a partner that is not your own) being detected.

The findings can help in fertility treatments since “ejaculate samples used to test for infertility are often collected with the use of images depicting women other than the man’s partner”.

“Our findings are the first to demonstrate that men’s ejaculate behaviour and composition change in response to novel female stimulus,” the authors concluded.