MONDAY, June 26 (HealthDay News) -- Scientists believe they've found a way to spot autism as early as birth by seeking out key biological abnormalities in the placenta.

Early diagnosis of autism, a developmental disorder that affects a child's social learning and communication skills, can greatly improve the chances for successful treatment, experts say.

Previous studies noted the presence of "trophoblast inclusions" -- an indicator of cellular abnormality -- in the placenta as a marker for Asperger Syndrome, an Autism Spectrum Disorder (ASD). Researchers at the Yale University School of Medicine studied the placentas of 13 children diagnosed with ASD to determine if there was a similar marker.

Compared to the placentas of 61 healthy children, the 13 placentas of Asperger-affected children were three times more likely to have trophoblast inclusions, the Yale team found.

"We knew that trophoblast inclusions were increased in cases of chromosome abnormalities and genetic diseases, but we had no idea whether they would be significantly increased in cases of ASD," study author Dr. Harvey J. Kliman, research scientist in the department of obstetrics, gynecology and reproductive sciences at Yale, said in a prepared statement. "These results are consistent with studies by others who have shown that ASD has a clear genetic basis," Kliman said.

Results of the study are published in the June 26 online issue of Biological Psychiatry. The researchers said they expected to further examine the presence of trophoblast inclusions as an indicator of ASD in future studies, with a larger study base and more in-depth analysis.

"If the work is confirmed by the next series of studies, then the finding of trophoblast inclusions at the time of birth in the absence of any obvious genetic abnormalities would be an indication to have a child examined by a specialist to determine the presence of ASD," concluded researcher Fred R. Volkmar of the Yale Child Study Center.