Advanced maternal age is linked to a significantly higher risk of having a child with autism, a new study has claimed.
The incremental risk of having a child with autism increases by 18 per cent, nearly one fifth, for every five-year increase in the mother’s age, according to a research by the scientists at the University of California.
A 40-year-old woman’s risk of having a child later diagnosed with autism was 50 per cent greater than that of a woman between 25 and 29 years old, the study said.
However, advanced paternal age is associated with elevated autism risk only when the father is older and the mother is under 30, said the article published in the journal Autism Research on Monday.
Advanced parental age is a known risk factor for having a child with autism. However, previous research has shown contradictory results regarding whether it is the mother, the father or both who contribute most to the increased risk of autism.
“This study challenges a current theory in autism epidemiology that identifies the father’s age as a key factor in increasing the risk of having a child with autism,” said lead author Janie Shelton.
“It shows that while maternal age consistently increases the risk of autism, the father’s age only contributes an increased risk when the father is older and the mother is under 30 years old,” Ms. Shelton said.
