Autism Risk Increases with Teen Moms, Fathers Over 40

Previous studies have delved into the risks teen dads take when they have children at such a young age. They not only run into life challenges, but also increase the risk of passing on genetic mutations to their offspring.

Autism Speaks added to this body of research when it recently funded one of the largest studies looking in to the relationship between parental age and increased autism risks. The analysis was quite large, including more than 5.7 million children in five countries.

Co-author Michael Rosanoff explained how researchers took data from “national health registries across five countries,” essentially “[creating] the world’s largest data set for research into autism’s risk factors. The size allowed us to look at the relationship between parents’ age and autism at a much higher resolution — under a microscope, if you will.”

Sven Sandin, a medical epidemiologist, explained in a press release:

“Although parental age is a risk factor for autism, it is important to remember that, overall, the majority of children born to older or younger parents will develop normally.”

“After finding that paternal-age, maternal-age, and parental-age gaps all influence autism risk independently, we calculated which aspect was most important. It turned out to be parental age, though age gaps also contribute significantly.”

Some of their key findings included increased risks of autism among older fathers. They found Autism rates were 66 percent higher among dads over 50 and 28 percent higher when dads were in their 40s compared to dads in their 20s. For mothers in their 40s the risk was 15 percent higher compared to mothers in their 20s. But on the opposite end of the age spectrum, teen moms had an 18 percent higher risk of having a baby born with autism compared to a mom in her 20s.

Co-author Abraham Reichenberg, a neuropsychologist and epidemiologist, noted:

“When we first reported that the older age of fathers increases risk for autism, we suggested that mutations might be the cause. Genetic research later showed that this hypothesis was correct. In this study, we show for the first time that autism risk is associated with disparately aged parents. Future research should look into this to understand the mechanisms.”

Indeed, while the data shows an interesting correlation between increased rates of autism in children born to older and younger parents on the age spectrum, it would be nice to pinpoint the cause. Assistant professor Michael Schatz, a quantitative biologist at Cold Spring Harbor Laboratory, is working on breaking down the pieces to figure out the cause.