The number of sperm is 50% lower in men whose father smokes: study

Although studies have repeatedly linked maternal smoking during pregnancy with reduced sperm count in male children, a new study has shown that men whose fathers smoked at the time of pregnancy were also a sperm count 50% lower than that of non-smoking fathers.

The results showed that, irrespective of the mother's exposure to nicotine, socio-economic factors and their own smoking, men whose father smoked had a sperm concentration of 41% lower and a number of sperm 51% lower than that of non-smoking fathers.

"I was very surprised to find that regardless of the mother's level of exposure to nicotine, the number of sperm of men whose fathers smoked was much lower," said Jonatan Axelsson, Medical Specialist. University of Lund in Sweden. "We know that there is a link between the number of sperm and the chances of pregnancy, which could affect the ability for these men to have children in the future.

"The father's smoking is also linked to the reduction in the reproductive life of girls, so the idea that everything depends on whether the mother smokes or not seems unconvincing," he added. However, the research did not determine the mechanisms underlying this situation. But similar studies have shown links between fathers smoking and various health problems in children, such as malformations, said Axelsson.

This may be because most of the new mutations (de novo mutations) come from the father, and there are also links between the father's age and a number of complex diseases, researchers said in a statement. newspaper published in the journal PLOS ONE. In addition, researchers have observed that smoking was related to damage of DNA in sperm and that smokers had more breaks in the DNA strand.

It is reported that children of smoking fathers have up to four times more mutations in a repetitive portion of DNA than children of non-smoking fathers. "Unlike the maternal egg, the father's gametes divide continuously throughout life and mutations often occur at the precise moment of cell division.

"We know that tobacco smoke contains many substances that cause mutations, so we can imagine that at the time of conception, the gametes mutated and transmit genes that lead to a reduction in the quality of the tobacco. semen in male offspring, "said Axelsson. The study was conducted on 104 Swedish men aged 17 to 20 years.