Examining a newborn’s placenta for abnormalities can identify the child’s risk for autism, according to a new study by researchers at the Yale School of Medicine.

The finding was published in the journal Biological Psychiatry and has shown that the identification of placentas with abnormal folds or cell growths known as trophoblast inclusions are key signs that can predict autism risk in infants.

One out of every 50 kids in the United States is diagnosed with an autism spectrum disorder each year, however, they are not usually diagnosed until the age of 3 or 4 years, according to the Centers for Disease Control and Prevention (CDC). By that time, the most successful opportunities for intervention are gone because the brain is most likely to make changes in the first year of life – it is much harder later on.

Senior author Harvey Kliman, M.D., research scientist in the Department of Obstetrics, Gynecology & Reproductive Sciences at the Yale School of Medicine, and research collaborators at the MIND Institute at the University of California, Davis, analyzed 117 placentas from newborns of at-risk families – those who had one or more child already with autism.

These families took part in a study named Markers of Autism Risk in Babies – Learning Early Risks. Investigators compared these placentas to 100 control placentas that were collected by UC David researchers from the same area.

The placenta keeps the unborn baby’s blood supply separate from the mother and gives the baby oxygen and nutrients. When the baby is born, the placenta follows the baby out of the womb.

The at-risk placentas had at least 15 trophoblast inclusions, and none of the control placentas had over two trophoblast inclusions.

Kliman suggested these findings imply that a placenta with four or more trophoblast inclusions can predict conservatively that a baby has a 96.7% likelihood of being at risk for autism.

To date, the most accurate predictor of autism risk is family history. Parents who have a child with autism are over nine times more likely to have a second child with autism. These families that are at-risk could implement the early intervention strategies to improve results with their other children.

Kliman concluded:

“Regrettably couples without known genetic susceptibility must rely on identification of early signs or indicators that may not overtly manifest until the child’s second or third year of life. I hope that diagnosing the risk of developing autism by examining the placenta at birth will become routine, and that the children who are shown to have increased numbers of trophoblast inclusions will have early interventions and an improved quality of life as a result of this test.”

The current study was built upon previous research from the Yale School of Medicine. Kliman and team examined the same topic on a smaller scale in 2006, analyzing the presence of trophoblast inclusions on the placenta. During that small study they also found this was a marker for autism.

Written by Kelly Fitzgerald