The study examined the medical records of nearly 3 million infants and found that children born with cytomegalovirus (CMV) were two and a half times more likely to be diagnosed with autism.
Although more research is needed, researchers believe the disease may cause inflammation in the fetus's brain, which can impair its development, said pediatrician Megan Bish, lead author of the study from the University of Michigan.
She revealed to the Daily Mail that her daughter was born with CMV and autism, despite appearing to be healthy at birth. She expressed her desire to raise awareness about the virus, so that screening during pregnancy becomes more common.
CMV is usually relatively harmless, and you may not even know your child has it, as there are no symptoms in most cases. Infection occurs when someone comes into contact with the saliva of an infected person.
When a mother is infected with CMV during pregnancy, it can pass through the placenta and infect the baby.
Some studies suggest that up to 90 percent of cases at birth may not be diagnosed, Bish said.
She explained that early screening for the virus (when babies are in the womb) could give doctors a chance to stop CMV before it harms the fetus's brain.
Autism results in a range of behaviors, and some common symptoms include: sensitivity to noise, difficulties interpreting social cues, and delayed language skills.
The study was published in the Journal of the American Academy of Pediatrics.