Male fertility may be compromised in hot tub users

Spending time in hot tubs and even hot baths may lead to male infertility, according to new research from the University of California, San Francisco. However, researchers said halting such exposure may reverse the effects.

The 3-year pilot study reviewed data from 11 men (mean age, 36.5 years), who were selected based on repeated exposure to wet heat via hot tubs, Jacuzzis, or baths. Study participants were to stop such exposure for at least 3 months. After 3 to 6 months, 45% of the men had positive results from stopping heat exposure-their mean increase in total motile sperm counts was 491%, as reported in the International Brazil Journal of Urology (2007; 33:50-7).

Researchers defined wet heat exposure as body immersion in a hot tub, heated Jacuzzi, or bath at a temperature warmer than body temperature for 30 minutes or more per week for at least 3 months before study enrollment. Those who had undergone infertility treatments in the prior year were excluded, as were those in which female infertility was a co-existing factor.

“We now have actual evidence to show patients that these recreational activities are a real risk factor for male infertility,” Paul J. Turek, MD, lead study author, said in a statement.

The study findings also showed that the negative effect of this exposure was reversed approximately one-half of the infertile men who halted such use. As for the six patients who did not experience increased sperm count or motility, tobacco use may have played a role. Five of the six patients were cited as chronic smokers, compared with three infrequent smokers in the group of responders.