Men maintain a certain level of reproductive function throughout life, but this function declines gradually over time. Studies have shown that advanced paternal age is associated with changes in reproductive hormone production, sexual function, sperm production and fertility, as well as an increased risk of sperm mutations, birth defects and offspring diseases. In fact, research found that increased mutations in children correlated with increased paternal age, not to increased maternal age.
Paternal age is also strongly associated with reduced fertility in couples where men are older than 40 and women are 35 or older. Changes in male hormones that occur with age, such as an increase in testosterone, tend to reduce the function of cells that support sperm cell production, resulting in reduced sperm count. In addition, increased age is associated with changes in normal sperm parameters, declining semen volume, sperm motility and structure, and changes in the integrity of chromosomes that can lead to genetic abnormalities.
These changes in sperm also affect the chances of fertilization through assisted reproduction technologies (such as in vitro fertilization). Moreover, a number of large studies have observed that paternal aging is associated with an increased risk of pregnancy loss after an established natural pregnancy.
These data provide some evidence that paternal age can affect sperm DNA integrity in a way that negatively impacts late embryo development. It’s not clear why these observed changes occur with age, but potential causes might include diseases that arise or get worse in middle age (such as atherosclerosis and diabetes) and the negative effects of lifestyle choices (related to diet, weight, alcohol or smoking). Indeed, since sperm production occurs throughout adulthood, as men age the testicular environment is more influenced by lifestyle insults, such as oxidative stress and decreased levels of protective micronutrients. As natural protections decline, sperm production becomes more sensitive to environmental stress, which affects DNA integrity and other sperm properties. Boosting fertility after age 35 requires lifestyle changes that include reducing alcohol consumption, quitting smoking, enjoying regular physical activity, following a healthy diet and taking natural nutritional supplements, such as Fruitful for Him.