You may have heard in the press of a claim that children born to fathers who were exposed to excessive heat during conception are more likely to suffer from brain cancer. The report claims that sperm may become damaged if exposed to excessive heat (such as being in a sauna or by using a electric blanket) and pass on genetic defects to the child.
It’s worth pointing out that the test sample was very small, 318, and that the researcher conceded that the evidence was speculative at this stage. However, that said, the testicles are kept outside the body for a reason – to keep at least 3 degrees below normal body temperature. So if you are planning on trying to conceive, it’s probably better to err on the side of caution and give the saunas a miss for the duration.
More information can be found on the BBC website.