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A father’s age at conception influences a child’s social behavior later on

The children of very young and very old fathers were most affected.   
Getty Images.
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People are having children later in life nowadays. They’re delaying marriage too. Millennials need to gain more education and spend a longer time in the workforce building up their career, in order to afford a wedding and children. So how is this shift affecting the next generation and society as a whole?


Many studies have focused on the impact an older mother has on a child’s development. For a woman, having a child later in life increase the risk of miscarriage, a difficult pregnancy, and the child having a developmental disorder. One plus side though, older women might parent better.  

Now, studies are turning toward older fathers. New research has shown that children born to a father over age 35 have a higher risk of autism, schizophrenia, or a birth defect. One study found that children born to dads over age 40 may even risk lower scholastic achievement.

Though slight, over an entire population, the impact could be significant. So much so, that one UK bioethicist has proposed a program to encourage 18 year-old’s to bank their sperm, and have the National Health Service (NHS) pay for it. The results of this study show that if such a plan were enacted, officials might want to wait to collect until the man was a little bit older.

Older fatherhood may increase the risk of lower scholastic achievement. Getty Images.

A new study finds that an older father is the single most important factor in a child’s development of prosocial skills. This was independent of the mother’s age. The results of this study were published in the Journal of the American Academy of Child and Adolescent Psychiatry (JAACAP). These include social skills such as helping, sharing, acknowledging the pain of others, and being considerate.

Researchers examined data from over 15,000 twins in the UK. Parents answered the Strengths and Difficulties Questionnaire (SDQ). This is a behavior evaluation tool for 3-16 year-olds used by clinicians, educationalists, and researchers. All of the subjects were part of another project called the Twins Early Development study (TEDs). Researchers examined the children’s records of social problems with peers, and instances of emotionality and hyperactivity. They also looked at the age of the father and any other relevant environmental or genetic factors.

What they learned was that certain prosocial aspects of a child’s personality and behavior are genetically driven. Those children born to a father under age 25 had better social behaviors when they were young. The same was true to those born to a father who was 51 or older. When children were born to a young or old father, when they became adolescents, their prosocial behavior lagged behind their peers. 

There might be an ideal window for when the right time is to farther children. Getty Images.

Dr. Magdalena Janecka was lead author of the study. She is a fellow at the Seaver Autism Center for Research and Treatment at Mount Sinai, in New York City. Dr. Janecka wrote in a press release, “Increased importance of genetic factors observed in the offspring of older, but not very young fathers, suggests that there could be different mechanisms behind the effects at these two extremes of paternal age.” She added, “Although the resulting behavioral profiles in their offspring were similar, the causes could be vastly different.”

This is the first study of its kind linking a father’s age to social behavior. Dr. Janecka hopes that this allows for a better understanding of how a father’s age effects his children. “In extreme cases, these effects may contribute to clinical disorders,” she said. “Our study, however, suggests that they could also be much more subtle.”

If the findings are corroborated, future research will investigate what mechanisms are at play, and what might be done to mitigate risks, besides of course, planning to have children at a younger age, which might not be possible for some men.

According to Dr. Janecka, “Identifying neural structures that are affected by paternal age at conception, and seeing how their development differs from the typical patterns, will allow us to better understand the mechanisms behind those effects of paternal age, as well as, likely, autism and schizophrenia.”

To learn more about how an older men’s sperms can influence his offspring, click here: 

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