The conversation we're not having about dads' biological clocks
The day after our first son was born, my wife, Elizabeth, and I saw a disturbing report on the news.
Researchers had found an increased risk of autism in the children of older fathers. Until then, we’d worried about Elizabeth’s age; she was 40. We worried about whether she’d be able to get pregnant, and we worried about the increased risk of Down syndrome in older mothers.
Now we had something new to worry about: I was 55, and we were hearing that my age could also pose a risk to our baby. I wanted to go home and forget I’d seen that report. But of course, I couldn’t.
In the years since, evidence has steadily grown that fathers — like mothers — have a biological clock. And the risks of autism, schizophrenia, bipolar disorder, and other disorders increase in children as the fathers get older.
The latest study, published this week in JAMA Psychiatry, found that children of fathers 45 or older had 13 times the risk of ADHD and 25 times the risk of bipolar disorder compared to the children of fathers 20-24 years old.
The children of the older fathers also had 3 1/2 times the risk of autism, nearly three times the risk of suicide, and almost 2 1/2 times the risk of problems with substance abuse.
These risks “are astonishing,” said the study’s principal author, Brian M. D’Onofrio, a clinical psychologist at Indiana University.
He and his colleagues were skeptical of their findings, and they ran multiple analyses to try to identify any error that could have crept into work. But “every way we did the analyses, we got the same results,” he said.
So, what does this mean for older couples thinking about having children? Women are generally well aware of the risks and difficulties associated with getting pregnant at an older age. Should men be similarly worried about their biological clocks?
D’Onofrio said he didn’t want to sound like a fearmonger. “We are not saying that every child born to an older man is going to have a psychiatric problem,” he told TODAY.com. “Most children of older men don’t have these difficulties.... I don’t want parents to say their kids are doomed if they had them at a later age.”
Nevertheless, “there is still an increased risk,” D’Onofrio said.
But that risk is seldom discussed, despite the growing body of research.
Even genetic counselors, who advise couples on such risks, often ignore the risks associated with older fathers, said Jehannine Austin, a genetic counselor at the University of British Columbia whose specialty is psychiatric genetic counseling.
“Medicine tends to focus on the role of mothers in bringing children into the world far more so than we do the role of fathers,” she said. “And I think that really should change.”
Sandra Darilek, an expert on prenatal genetic counseling, says it is still unclear what to do about the risks associated with older fathers.
“There aren’t guidelines about what you should and shouldn’t expect with regard to paternal age,” she said. “Older fathers have a higher risk of passing on what we call new mutations. The problem is that there isn’t any prenatal test that will identify that.”
Furthermore, counselors often do not see couples until the woman is already pregnant, she said. And then it might be wiser not to tell couples about the increased risks associated with fathers’ age. “We’d just be alarming couples when we have nothing to offer them,” she said.
D’Onofrio’s research found that risk increased steadily as fathers aged. There was no age at which the risk zoomed up. Instead, the older the father was, the greater the risk to his children.
“Everyone wants to know when it is safe to have children and when it is not safe,” D’Onofrio said. “There is an increasing risk as men get older. There is not a safe age and a risky age.”
Our two boys are now 7 and 4 — yes, we had another one knowing the risks — and they are fine. We have years to go before we will know for sure whether they have avoided the risks related to my age, but Elizabeth and I have not had any second thoughts about our choices.
Paul Raeburn is the author of the forthcoming book, "Do Fathers Matter? What Science Is Telling Us About the Parent We’ve Overlooked."