Researchers at McGill University in Montreal, Children's Hospital Boston, Harvard Medical School and Brigham and Women's Hospital collected pertinent demographic, prenatal, intra-partum, acute postnatal and short-term outcome data for all infants.

The infants underwent conventional magnetic resonance imaging studies at preterm and/or term-adjusted age, with a follow-up at about 22 months.

The researchers used the Modified Checklist for Autism in Toddlers, the Vineland Adaptive Behavior Scale and the Child Behavior Checklist.

The study, published in the journal Pediatrics, found early autistic behaviors seem to be an under-recognized feature of very low-birth weight infants.

The researchers said the findings suggest that early screening for signs of autism may be warranted in this high-risk population, followed by definitive autism testing in those with positive screening results.