Babies who require resuscitation at birth and subsequently remain healthy may still be at risk for having a low IQ when they reach 8 years of age, according to a new study.

Mild physical difficulties early in life might be enough to cause nerve damage, and thereby affect IQ in childhood and possibly later in life, Dr. David E. Odd and associates, from the University of Bristol, UK, say in their report in The Lancet medical journal.

Their analysis included almost 6000 infants from the Avon Longitudinal Study of Parents and Children who were born in 1991 and 1992 and were tested for IQ at an average age of 8 years. Of these infants, 400 required resuscitation at birth, but had no evidence of injury, whereas 26 required resuscitation and had immediate signs of brain damage.

Low IQ scores were seen in 10 percent of resuscitated infants without injury and in 23 percent of those with brain damage. By comparison, just 7 percent of infants not requiring resuscitation had low IQ scores.

In a related editorial, Drs. Maureen Hack and Eileen Stork at Case Western Reserve University in Cleveland, comment that future studies using blood tests, x-rays, and other assessment methods are needed to verify and expand on the findings.

SOURCE: The Lancet, online April 21st, 2009.