Autism linked to preeclampsia, study suggests

Researchers in California have discovered a link between autism spectrum disorder (ASD) and preeclampsia.

A study of more than 1,000 children between the ages of two and three found that children diagnosed with ASD were more than twice as likely to have been exposed to preeclampsia in the womb.

The likelihood of the child being diagnosed with ASD was even greater when the mother’s disease was more severe, the study found.

Preeclampsia is a condition marked by high blood pressure, which typically develops in the second half of pregnancy.

Symptoms include elevated protein levels in the urine, as well as edema, or fluid retention.

“We found significant associations between preeclampsia and ASD that increased with severity,” senior study author Cheryl Walker, an assistant professor in the Department of Obstetrics and Gynecology Division of Maternal Fetal Medicine and a researcher with the UC Davis MIND Institute, said in a statement.

“We also observed a significant association between severe preeclampsia and developmental delay.”

The findings were published Monday in the online edition of the journal JAMA Pediatrics.

Included in the study were more than 500 male and female children who had been diagnosed with autism, another 200 children with developmental delays, and 350 children who were developing normally.

All of their mothers had been diagnosed with preeclampsia.

In addition to the link between preeclampsia and ASD, the study found that mothers of children with autism and of children with developmental delays were also “significantly more likely” to have had placental insufficiency, or both placental insufficiency and preeclampsia.

Placental insufficiency occurs when the placenta cannot deliver an adequate supply of nutrients and oxygen to the fetus. This can happen when the placenta does not properly develop, or when it becomes damaged.

The study also found a correlation between preeclampsia and developmental delay without autism, particularly in cases involving placental insufficiency.

Previous research has probed a potential link between preeclampsia and autism, but the findings have been inconsistent. While the current research is larger and includes strict controls, a single study cannot prove causality, Walker notes.

However, “the cumulative evidence supports efforts to reduce preeclampsia and diminish severity, to improve neonatal outcomes.”