Timing of prenatal CMV infection may determine likelihood of ASD diagnosis

Researchers in France report that children infected with cytomegalovirus (CMV) in utero have elevated odds of developing an autism spectrum disorder (ASD), but only if their mothers’ infection occurred during the first trimester of pregnancy.

Marianne Leruez-Ville and colleagues analyzed data on 642 children with confirmed congenital CMV infection. They say, “Long-term congenital CMV-related sequelae, including hearing loss and neurodevelopmental impairment, were observed exclusively in children exposed to first-trimester maternal primary infection. Autism spectrum disorder was diagnosed in 11 children (1.7%), all of whom were symptomatic at birth; all cases following maternal primary infection occurred after first-trimester exposure.” Autism prevalence in children with congenital CMV was four times higher than in the general population, and all children diagnosed with ASD exhibited temporal lobe white matter anomalies.

The researchers conclude, “These findings support a time-restricted window of fetal vulnerability to CMV-related brain injury and suggest that neuroimaging findings may contribute to prenatal and neonatal risk stratification and help inform prenatal and postnatal counseling.”

Citations

“Maternal cytomegalovirus infection in the first trimester of pregnancy: timing, fetal brain injury, and long-term neurodevelopmental outcomes including autism spectrum disorder,” Marianne Leruez-Ville, David Grevent, Nicolas Bourgon, Christos Chatzakis, Marine Parodi, Jacques Fourgeaud, Nicolas Veyrenche, Nadia Bahi-Buisson, Christine Pichon, Jean-Francois Magny, Nathalie Boddaert, and Yves Ville, American Journal of Obstetrics and Gynecology, May 2026 (online). Address: Marianne Leruez-Ville, Université Paris Cité, URP 7328 FETUS, F-75015 Paris, France.