Frequent visits to the sauna may lower men's sperm count, temporarily, due to increased temperatures, a new study claims.
In the study by the University of Padova in Italy, healthy Finnish men in their 30s with normal sperm counts spent 15 minutes in a sauna two times a week for three months, after which they stopped visiting the sauna.
The sauna sessions lowered the men's sperm counts, and they remained below normal for three months after the men stopped visiting the sauna.
However, after six months, sperm counts returned to normal, 'MyHealthNewsDaily' reported.
The findings make sense because higher temperatures are known to affect sperm production, said Dr Andrew Kramer, a urologist at the University of Maryland Medical Center.
Researchers said men with undescended testicles can have impaired sperm product and fertility, adding, during the sauna sessions, scrotal temperatures increased by 3 degrees Celsius.
However, the new study did not assess the men's fertility, so it was not possible to know whether their fertility was lower during the period they took saunas, Kramer added.
Researchers also found that sauna exposure affected the way DNA was packed into the sperm cells, and impaired the mitochondria, the cell's powerhouse. This might explain why sperm production is less efficient during sauna exposure, the researchers said.
"Avoidance of testicular heating and in particular of sauna exposure (in those countries where sauna is largely used) could be suggested in the counselling of males seeking fertility [treatment]," said researcher Carlo Foresta, a professor of endocrinology.
However, Kramer said the study, published in the journal Human Reproduction, does not provide enough evidence to say that healthy men should not visit the sauna.
