Toxic Tubbing: Hot Tubs‘ Effects on Male Fertility
Quiet. Warm. Relaxing. Soothing. How can a hot tub or a steaming hot bath possibly be bad for your health? Well, they are…for men. They reduce male fertility. Big time.
The History of Heat and Fertility
Elevated temperature has been a recognized cause of impaired sperm production since the time of Hippocrates. Even a simple fever can hurt the sperm factory. In the 1940s, Dr. Martha Voegeli, a Swiss doctor in India, reported a simple heat regimen for male contraception. Her protocol involved having men sit in a hot bath (116o F) for 45 minutes daily for 3 weeks. Six months of infertility resulted from this exposure, after which normal fertility returned! A modern example of heat affecting fertility is the postulated heating of the scrotum with laptop computers. Kind of makes you wonder about the effects of triple-digit heat waves in the U.S. on baby-making efforts.
Heat: The Real Deal
These stories intrigued me and led me to publish a study on the effects of hot tubs and baths on male fertility. We asked whether the withdrawal of such exposures in men with poor semen quality could lead to improvements in semen quality. We also looked for factors that might influence the response to stopping the heat exposure.
In our study, men were evaluated before and after exposure to wet heat in the form of baths and tubs. Among them, 45% responded favorably to withdrawal from heat exposure, with a mean increase in moving sperm counts of almost 500%. If sperm were money, they would be rich! Some men started out with no sperm (azoospermia) and had a return of sperm to the ejaculate. The problem is that it took 3 to 6 months to see the change, reflecting the time it takes to make and ejaculate sperm. Among those who didn’t respond, many were tobacco users (makes sense: take a tub and light one up).
We concluded that tubs are toxic to semen quality. The New York Times release of our paper’s findings included a figure of a man in a hot tub thinking about how much better hot tubs are than condoms or birth control pills for contraception. Just as importantly, our study showed that the damage to semen caused by hot tubs is reversible in many cases. The reversibility takes time, though.
How Does Heat Impact Sperm Production?
Testes are weirdly fascinating organs—they function best at a temperature 3 degrees cooler than the rest of the body. That’s why they hang outside in the scrotum. In fact, there’s a muscle called the cremaster that’s responsible for regulating scrotal temperature by raising or lowering the testes. Yes, temperature is so closely tied to sperm production that there’s a built-in cooling system to support the process! But things can go awry with excessive heat, like the kind encountered in a hot tub or sauna.
Heat disrupts the efficiency of enzymes working hard during spermatogenesis, the delicate process of making sperm. As a result the high temperatures lower sperm count, reduce motility (the ability to swim), and alter sperm morphology (shape). Fewer good-looking swimmers is the consequence.
But heat can have other effects on sperm. It also ramps up oxidative stress in the testes, which may damage the DNA package inside sperm cells. Damaged sperm DNA means that it won’t perform as well, impairing egg fertilization and embryo development. So, fewer high performing, fertile sperm is another consequence.
Practical Tips to Protect Male Fertility from Heat
Men trying to conceive can take the following steps to minimize the impact of heat on sperm health:
- Avoid hot tubs, saunas, steam showers and hot baths during fertility planning.
- Wear loose-fitting, breathable underwear to allow good heat ventilation down there.
- Stay hydrated during exercise or hot weather, as dehydration can further elevate body temperature.
- Be aware of subtle occupational heat exposures from working in heat-rich environments like kitchens, rooftops or wearing hot uniforms, or using heated car seats.
- Take breaks during activities like cycling or sitting for extended periods, activities which can raise scrotal temperature due to the lack of the scrotum’s ability to self-regulate temperature.
- Seek medical advice if fertility concerns persist, as addressing underlying issues early can improve outcomes.
Discuss Fertility Issues with a Leading Expert
So, if you’re a man who cares about his fertility, avoid hot tubs, baths and saunas. While these may be the last things on your dehydrated mind as you swelter in the summer heat or after exercise, keep this in mind as you consider romantic ways to make hay.
To learn more ways to maximize your fertility, please schedule an appointment at the Turek Clinic. Call 1-888-TUREKMD today.
