Fertility: Age also affects men

For men, too, age matters when it comes to fertility and can even lead to a missed opportunity: having a child. Recent scientific research has clearly confirmed that a man's age impacts reproductive success, especially in the case of assisted reproduction.

As we know, theandropause, similar to menopause, does not exist, but male fertility changes, and quite significantly, with advancing age.

First After the age of 35-40, the quality and quantity of sperm decrease, but not only that: their motility, meaning their ability to move, and their morphology (i.e., their shape) are reduced, with an increase in errors in DNA replication that translates into an increased risk of miscarriage. Added to this is the progressive decline in testosterone and a reduction in sperm motility.

Furthermore, with advancing age the risk of sperm DNA fragmentation increases significantly, a damage that further compromises fertilizing ability.

Science has established the range of theright age for a woman, during which to have a child. But for men, couples with male partners over 45 can take much longer to achieve pregnancy, and the advanced age of the father also increases the risk of neurodevelopmental disorders, even serious ones (primarily autism and schizophrenia) and other types of genetic malformations.

A June 2025 study published in the scientific journal Human Reproduction has shown that a man's age influences fertility and reproductive outcomes, even in the case of assisted fertilization with young oocytes.

Men over 45 can take up to 5 times longer than younger people to achieve pregnancy. The most important findings of the study, which divided participants into two groups (under and over 45 years of age) and examined 1.712 assisted reproduction cycles performed in Italy and Spain, were the following:

• Miscarriage rates were significantly higher in fathers over 45 years of age (23,8 percent compared to 16,3 percent in younger men).

• Live births were less frequent in groups with older men (35,1 versus 41 percent)

This study is yet another scientific confirmation that the old idea that “men can be equally fertile at any age” is unfounded.

In reality, men also have a biological clock, and fertility and reproductive outcomes tend to worsen with age, especially after 45. These are all factors to keep in mind so as not to waste the joy of fatherhood.

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• How to protect fertility
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