Babies born just a couple weeks early are more likely to test poorly in grade school.
A new study out of Columbia University looked at more than 100,000 babies born between 37 and 41 weeks gestation. The birth records were matched with the babies' third-grade math and reading test scores.
They found those born at 37 and 38 weeks gestation, technically considered "at term" deliveries, were more likely to have a reading impairment and score lower on math tests.
Experts say the fetal brain is rapidly developing during the last weeks of pregnancy, and an early delivery may disrupt the process.
The effect of early delivery remained even when researchers accounted for other factors like birth weight, and social/economic factors.