With a summer as hot as the one we've just had, many of us have likely stripped down to our underwear to help keep cool in bed.
But according to experts, this could be doing more harm than good - with scientists claiming that sleeping in your pants could lead to a host of health problems.
This is supposedly because constricting underwear affects the body's ability to regulate temperature and hygiene between fabric and the skin, creating problems including irritation and infection.
Dr Brian Steixner, of the Institute for Men's Health in the US, even warned that men who sleep in boxers or briefs can end up compromising their fertility, saying: "Your nether regions need to be just the right temperature to optimise sperm production."
Dr Alyssa Dweck, a fertility expert from New York, said it is better to strip off completely at night to let your nether regions "breathe", adding: "I often tell my patients to sleep without underwear. If the area is constantly covered - especially by a fabric that's not moisture-wicking or absorbent - then moisture collects, creating the perfect breeding ground for bacteria or yeast."