New research babies that are heavier at birth could have a slight academic advantage later in life.
Findings suggesting heavier newborns do better in elementary and middle school than those with a lower birth rate, Northwestern University reported. These results back up the idea that fetuses benefit from spending more time in their mothers' wombs.
"A child who is born healthy doesn't necessarily have a fully formed brain," said David Figlio, one of the study's authors and director of Northwestern's Institute for Policy Research (IPR). "Our study speaks to the idea that longer gestation and accompanying weight gain is good. We want to know: What does that mean for public policy?"
The research shows babies who weigh more at birth have higher test scores between the third and eighth grades. Even among twins, the one who was heavier at birth tended to do better on tests during this age range. Attending a higher quality school did not appear to make up for the disadvantage of having a low birth weight. The advantage was seen in babies across all races and socioeconomic factors.
"The results strongly point to the notion that the effects of poor neonatal health on adult outcomes are largely determined early -- in early childhood and the first years of elementary school," the researchers wrote in the study.
The researchers made their finding by looking at merged birth and school records of Florida children ath were collected between 1992 and 2002 encompassing 1.3 million children and nearly 15,000 pairs of twins.
"It will be valuable to learn whether improvements in earnings by families with pregnant women, improved maternal nutrition or reduced maternal stress -- all factors associated with higher birth weight -- also translate to better cognitive outcomes in childhood," Figlio said.
The researchers noted other factors, such as whether or not the infant's mother graduated college, could trump the birth weight advantage.
"You'd rather be a low birth-weight baby with a mother who has a college degree, than a heavier baby, born to a high school dropout," said study coauthor Jonathan Guryan.
The findings were published e Dec. 14 in the journal American Economic Review.
