Health News

NEW YORK (Reuters Health) - Babies born weighing less than 2.2 pounds (1,000 grams) may grow up to be shy, timid adults. Researchers found that young adults born at this extremely low birth weight were often more cautious and shy and less outgoing than young adults who were normal weights at birth. They were also less apt to be risk-takers.

"This personality style is also characterized by a decreased probability to engage in some social situations and subsequently an increased chance of experiencing loneliness and lowered emotional well being, possibly placing them at risk for psychiatric problems, researchers from McMaster University, Hamilton, Ontario, Canada report in the journal Pediatrics.

"The finding," Dr. Louis A. Schmidt told Reuters Health, "may have at least theoretic implications in terms of how we view emotional development in children; adverse life events may in fact bias some individuals to develop shyness and we know that in typically developing children shyness can be a risk factor for later problems."

Schmidt and colleagues studied 71 young adults born early weighing between 501 to 1,000 grams (1.1 to 2.2 pounds) and 83 young adults born at term of normal weight.

They found that the personalities of the two groups of young adults differed markedly.

Personality tests showed that the adults born at extremely low birth weight reported significantly higher shyness ratings and were also more inhibited and less social than the adults born at normal weight. The extremely low birth weight group also had lower scores on measures of emotional well-being than their normal weight counterparts.

Overall, these results, note Schmidt and colleagues, "replicate and extend" those of other recent studies, which have noted personality differences among adult survivors of very preterm birth, including higher rates of neurosis, cautiousness and lower extraversion.

SOURCE: Pediatrics July 2008.