Study looks at boxer shorts versus underpants and sperm count

By Dr. Ananya Mandal, MDAug 8 2018

A new study from the Harvard’s T.H. Chan School of Public Health has shown that loose underwear such as boxers may be better for sperm counts in men when compared to tight ones such as briefs.

Dr. Jorge Chavarro, associate professor of nutrition and epidemiology at Harvard, lead author of the study has explained that tight underwear in men such as briefs can raise the scrotal temperatures and this can contribute to a lower sperm count and infertility. The study was published this week in the latest issue of the journal Human Reproduction.

Sperm cells 3D rendered illustration. Image Credit: Vchal / Shutterstock

According to Chavarro, this study was just a proof of what was speculated from earlier smaller studies. He explained that for men who are having difficulty conceiving or are trying to conceive, it may be a good idea to pay heed to the results of this study. For this study the team looked at 656 men over a 17 year period between 2000 and 2017.

The men were aged between 32 and 39 years. Chavarro said that men who chose to wear boxers were found to have a higher concentration of sperm compared to those who wore tight underwear. The levels of follicle-stimulating hormone or FSH was found to be higher among men who wore briefs regularly. FSH is the hormone that stimulates the testes to produce sperm. Higher levels of FSH indicate that the body is pushing the testes to produce more sperm as counts are low.

The study included men who visited the Massachusetts General Hospital for fertility problems. Nearly half of the men – 345, said that they preferred boxer shorts over bikini briefs for men. The men were asked to provide blood and semen samples and were asked about their choice of underwear. From the semen samples the team of researchers looked at total count of sperm, motility of the sperms, morphology or appearance of the sperm and the extent of DNA damage to the sperm. Choice of underwear seemed to affect only the total count of the sperm and the other parameters remained unaffected.

Results showed that men who preferred boxers had a 25 percent higher sperm concentration and a 17 percent higher sperm count. Their sperm were 33 percent more motile. Further the levels of their FSH was 14 percent lower.

There have been several studies of late that show that there is a steady decline in sperm counts. The cause behind such fall is unknown say experts. They add that for men with fertility problems, loose underwear has been advocated before. This study adds to the scientific basis to that advice. Lidia Mínguez-Alarcón, author and a research scientist at Harvard's T.H. Chan School of Public Health also said that this study provides science behind the recommendation for loose underwear to men who have fertility problems.

According to Chavarro, not all men need to change their underwear overnight but those who are having trouble conceiving should consider boxer shorts over briefs.