Causes of autism: Could delayed childbearing, infertility treatment, and premature birth contribute to autism?

Link Research … suggests the answer is yes. … At this point, experts can only guess at the biological basis for the links they're finding. And those clues are not enough to recommend changes in, for example, infertility treatment.

Still, knowing who may be at risk of autism could improve diagnosis, which might enable earlier intervention. One study … followed babies who weighed less than 4.4 pounds at birth through to age 21. Nearly 5 percent of these 623 young adults had an autism-spectrum disorder, five times the rate in the general population.

... In recent decades, women have been delaying motherhood, which increases both their chance of needing fertility treatment, and their chance of having a low-birth-weight baby, typically due to prematurity.

These changes have emerged as risk factors for autism: Two studies … linked infertility treatment to the chance of autism … ovulation-inducing drugs … nearly doubled the odds of having an autistic child … autistic children … were three to four times more likely to have been conceived through in-vitro fertilization and to have been born at very low weights than children in the general population. The mothers of autistic children were also older …