Tight Underwear Linked to Poorer Semen Quality
A study of 26,836 men found tight underwear is associated with lower semen quality and quantity, along with higher rates of erectile dysfunction and premature ejaculation.
Updated on Nov. 5, 2026 in Men’s Health
Researchers at the University of Science and Technology of China found that men who wore tight underwear had poorer semen quality and lower semen quantity than those who wore looser styles. The study, which enlisted 26,836 men, was published in the Asian Journal of Andrology.
Why it matters
Poor-quality semen is the most common cause of male infertility, making underwear choice a question of interest to men trying to conceive. The findings also link tight underwear to higher prevalence of erectile dysfunction and premature ejaculation.
The study surveyed 26,836 men on their underwear preference before analyzing semen samples, and tight briefs raise scrotal temperature by 0.5°C-1°C compared with looser styles. Whether loose underwear improves fertility remains uncertain.
The players
University of Science and Technology of China
A public research university in Hefei, Anhui, China, known for its strong programs in the natural sciences and engineering.
Asian Journal of Andrology
A peer-reviewed scientific journal published by the Chinese Medical Association that covers research on male reproductive health.
The details
Participants reported whether they wore loose or tight underwear and then provided a semen sample for analysis. Researchers explain that tight underwear raises temperature inside the scrotum, which can impair sperm storage in the epididymis and the final stages of sperm development.
Timeline
The study findings were published on November 5, 2026.
Health Landscape
Research on male fertility has increasingly examined everyday factors such as heat exposure, and this study adds underwear fit to that line of inquiry. Findings like these are published in venues such as the Asian Journal of Andrology, which tracks reproductive health research globally.
Men who want to protect semen quality may consider switching to looser-fitting underwear, since the study links tight styles to higher scrotal temperature. The findings do not yet prove that switching will improve fertility, so men with concerns should discuss them with a doctor.
The takeaway
Choosing looser underwear costs nothing and may help reduce scrotal heat, though the fertility benefit is still unconfirmed. Men experiencing fertility or sexual health problems should consult a healthcare provider.
Further reading
For related coverage of male reproductive wellness, explore our Men's Health section.
