Hot tubs or hot baths can lead to male infertility, according to a small pilot study in Brazil.
A three-year study analyzed data from 11 infertile men who had been repeatedly exposed to high water temperatures through hot tubs or hot baths, the study reported in the March-April issue of the International Brazilian Journal of Urology.
"It has been believed for decades that wet-heat exposure is bad for fertility, as an old wives' tale, but this effect has rarely been documented," said study leader Dr. Paul J. Turek, a urologist and professor at the University of California, San Francisco. "We now have actual evidence to show patients that these recreational activities are a real risk factor for male infertility."
For the purposes of the study, wet-heat exposure was defined as the immersion of the body in a hot tub or bath at a temperature warmer than body temperature for 30 minutes or more per week for at least three months prior to participation in the study.