(NBC News) Could it be that men have a biological clock as well?
A new study links autism, ADHD and other mental health problems in kids with the age their fathers were when the babies were conceived.
Compared to men who father children in their 20s, men in their 40s are more likely to father babies who later have autism, attention deficit hyperactivity disorder and suicidal behavior among other psychiatric problems.
Doctors at Indiana University analyzed data on everyone born in Sweden between 1973 and 2001, roughly 2.5 million people.
The researchers found kids born to fathers in their 40s were three and a half times more likely to develop autism than their peers with younger dads, twice as likely to have a psychiatric disorder and 13 times more likely to have ADHD.
Outside experts offer caution and perspective.
"Even if I tell you that your risk of autism is up three times greater than normal, that means there's a 97% chance you will not have a child with autism," says Dr. Max Wiznitzer.
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