Sauna use raises scrotal temperature, which can temporarily reduce sperm count and motility. Managing scrotal temperature during sessions keeps the testicles cooler while the body takes the heat.
How Sauna Use Affects Sperm Production
Sauna use raises scrotal temperature, which can temporarily disrupt sperm production. Sperm production is highly temperature-sensitive and operates best when scrotal temperature stays several degrees Fahrenheit below core body temperature. [1] When scrotal temperature rises, sperm count, motility, and morphology all measurably decline. [2] This effect is reversible, with parameters recovering over the following months once scrotal temperature returns to normal. [2]
Why Scrotal Temperature Matters
The testicles sit outside the body because they are built to run cooler than core body temperature. This temperature gap is critical for optimal sperm production. [1] When heat exposure closes this gap, the biology suffers. Studies show that sauna sessions can elevate scrotal temperature enough to temporarily disrupt sperm production. [2]
The Sauna Effect on Sperm Parameters
Research has shown that two 15-minute sauna sessions per week for three months significantly reduced sperm count and motility. [2] The effect was reversible, with parameters recovering over the following months once scrotal temperature returned to normal. [2] This aligns with broader findings that elevated scrotal temperature is associated with lower sperm concentration. [3]
The Practical Takeaway
Whole-body heat is good for men, and the testicles are a part that does better staying cool while the rest of the body takes the heat. The fix is mechanical, not behavioral. Give them airflow, keep moisture moving, and bring the temperature down directly during the session.
Where Oakman Fits
Oakman is built to solve exactly this problem, starting with the part no ordinary underwear has: a removable cold pack in a medical-grade nylon shell that sits in a front pocket and rests against the scrotum through a layer of soft fabric during a sauna session, cooling the testicles right where heat rises fastest while the rest of the body takes the heat. The brief around it keeps the area cool the rest of the day too. The fabric is Siro-spun TENCEL-branded MicroModal, a soft, breathable natural fiber made from wood pulp that moves moisture better than polyester, which is less breathable and sheds microplastics, or cotton, which holds sweat. As a natural fiber, TENCEL-branded MicroModal doesn't shed microplastics the way synthetics do. An athletic gusset gives the testicles room and airflow instead of pressing them tightly against the body. Fabric, fit, and active cooling work together to keep the testicles closer to the temperature range they are designed for.
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Frequently asked questions
Does sauna use affect fertility?
Sauna use raises scrotal temperature, which can temporarily reduce sperm count and motility. Managing scrotal temperature during sessions keeps the testicles cooler while the body takes the heat.
How long does it take for sperm parameters to recover after sauna use?
Parameters typically recover over the following months once scrotal temperature returns to normal.
What is the best underwear for sauna use?
The best underwear for sauna use combines a breathable natural fiber like TENCEL-branded MicroModal, an athletic fit with a gusset for testicular airflow, and an integrated cold pack worn during the session to bring the temperature down directly.
This guide is educational and not medical advice. Heat's effect on testicular cell function and sperm is shown in cellular and animal research; whether it shifts a healthy man's testosterone levels long-term is not established. These statements have not been evaluated by the FDA. Oakman is not intended to diagnose, treat, cure, or prevent any disease or condition, including infertility or changes in testosterone, and makes no claim to increase testosterone or improve fertility or sperm quality. Individual results vary. Consult a qualified healthcare professional before changing your health routine.
References
- Durairajanayagam D, Agarwal A, Ong C. (2015). Causes, effects and molecular mechanisms of testicular heat stress. Reproductive BioMedicine Online. [Link]
- Garolla A, et al.. (2013). Seminal and molecular evidence that sauna exposure affects human spermatogenesis. Human Reproduction. [Link]
- Hjollund NHI, et al.. (2002). Impact of diurnal scrotal temperature on semen quality. Reproductive Toxicology. [Link]
