Virility

[2] Virility is commonly associated with vigour, health, sturdiness, and constitution, especially in the fathering of children.

[3] Historically, masculine attributes such as beard growth have been seen as signs of virility and leadership (for example in ancient Egypt and Greece).

However, an even larger difference is seen in how many of the seminiferous tubules in the testes contain mature sperm: Research shows increased risks for health problems for children of older fathers.

A large-scale Israeli study found that the children of men who were 40 or older were 5.75 times more likely than children of men under 30 to have an autism spectrum disorder, controlling for year of birth, socioeconomic status, and maternal age.

[8][9][10] Researchers have found evidence to suggest overweight and obesity may cause subtle damage to sperm and prevent healthy pregnancy.