Research shows that older parents are more likely to have children with autism than younger parents. A study from Drexel University School of Public Health in Philadelphia and Karolinska Institute in Sweden provides new information into how the risk associated with parental age varies between mothers’ and fathers’ ages. They also found that the risk of having a child with both autism spectrum disorder (ASD) and intellectual disability is larger for older parent. Mothers’ and fathers’ advancing ages have different impacts on the child’s health risks. The rise in ASD is linked more to older moms than older dads.
Yes, but why?
“The open question at hand really is, what biological mechanisms underlie these age effects?’ explained Brian K. Lee, PhD, an assistant professor in the Drexel University School of Public Health and research fellow of the AJ Drexel Autism Institute, a senior author of the study. The risk of having a child with ASD has a more complicated relationship to age in women than in men. For women who have children before age 30, there is little risk of ASD. But after 30 something happens since the chance of developing ASD rises rapidly.
There could be many reasons
Multiple mechanisms could be in play. These include environmental risks for women over 30. Complications in pregnancy cold underlie the age issue. For men the increased risk is more linear and coincides with naturally occurring genomic alterations over a father’s lifetime.
Not an easy study to perform
“When considering risk factors, we can’t necessarily lump all ASD cases together, even though they fall under a broad umbrella of autism,” Lee noted. “We need to keep an open mind in case intellectual disability might be a marker of a different underlying mechanism.” Still, the overall risk is low. “The absolute risk of having a child with ASD is still approximately 1 in 100 in the overall sample, and less than 2 in 100 even for mothers up to age 45.”
Source: MedicalNewsToday, International Journal of Epidemiology