The research suggests that babies who weigh more at birth have higher test scores from third through eighth grade. The relationship is apparent even among twins; heavier-born twins have higher average test scores in third through eighth grade than their lighter-born twin.
Even the advantage of attending a higher quality school was not enough to compensate for the disadvantage of a lower birth rate, according to the study. The low birth-rate advantage held up across the board for all children -- regardless of race, socioeconomic status, enrichment experiences provided by parents, maternal education and a host of other factors.
Researchers merged birth data and school records of all children born in Florida between 1992 and 2002 -- that's more than 1.3 million kids -- to reach these conclusions. However, in an article in The New York Times, study co-author David N. Figlio said this is most likely the first of many more studies that will be conducted on this subject, mentioning that weight may just be "a proxy for other aspects of fetal health that more time in the womb would not improve."
It's also important to note that babies born at a higher birth weight can also often be, depending on their weight, at an increased risk for a number of other health complications. And birth weight is definitely not the end all, be all for your child's success in school—take a look at these 15 ways you can boost your child's success in school.
Photo of little girl courtesy of Shutterstock.