These undies probably give dads-to-be stronger swimmers, according to science

Man wearing jeans

Good news for dads or dads-to-be who are trying to conceive a wee baby – New research has just confirmed the best undies to wear if you want to live your best sperm so thank you very much, science! 

Think inside the box(er)

The largest study yet of gents’ smalls has found that what we suspected is likely true – that men who wear boxer shorts have more sperm than men who wear the snugger brief underwear option, according to a paper published on Wednesday in medical journal Human Reproduction.

The Massachusetts-based study looked at 656 men between the ages of 18 and 56. These obliging men gave researchers a semen sample and blood sample on the same day, as well as responding to a questionnaire about the types of undies they wore in the preceding months. 


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33 percent more swimmers

When the results came in they showed there was a marked difference in men’s sperm quality and they hypothesise that the undies played a big role in this.

“Men who primarily wore boxer shorts had a statistically significant 25 percent higher sperm concentration, 17 percent higher total sperm count, 33 percent more swimming sperm in a single ejaculate … then men who did not usually wear boxer,” the study results say.

As you can see the boxer-wearing gents’ sperm was made of much stronger stuff than their snug-brief-wearing counterparts.

The study also found that men who wore boxers “tended to be younger, slimmer and more likely to take hot baths or Jacuzzis than the men who wore other, more tightly fitting underwear,” which seems borderline judgemental, if you ask us.

Why tho?

Scientists are still working out why the loose pants made such a big difference to the swimmers, and figure that other factors to do with how hot testicles get beneath clothing might come into play.

It’s “not possible to prove from these findings that the type of underwear causes the difference in semen quality and FSH levels, only that there is an association between them. Other factors that might affect scrotal heat, such as the type of trousers (e.g. skinny jeans) and underwear fabric, could also affect the results,” the researchers say.

Moral: Keep your scrotums cool, dads-to-be.

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