Previous research has found that infants born at 34 to 36 weeks’ gestation – classified as “late preterm” – have an increased risk of developmental delays and other mental and medical difficulties. A new study suggests even infants born at 37 or 38 weeks’ gestation -- technically “at term” – are at risk.
The study, “Academic Achievement Varies With Gestational Age Among Children Born at Term,” in the August 2012 Pediatrics (published online July 2), analyzed data from 128,000 babies born between 37 and 41 weeks’ gestation in New York City.
Birth records were matched with public school records of standardized third-grade math and reading tests. Researchers found achievement scores for children born at 37 and 38 weeks were significantly lower than those of children born at 39, 40 or 41 weeks. Compared to children born at 41 weeks, children born at 37 weeks have a 23 percent increased risk of having a moderate reading impairment; children born at 38 weeks have a 13 percent increased risk. Math scores were also lower for children born at 37 or 38 weeks. The effect was independent of birth weight and other obstetric, social and economic factors. The infant brain grows rapidly in the last weeks of gestation, and may be more likely to be disrupted when children are born early, even within the commonly defined period of term gestation.
Study findings suggest this disruption may affect later academic achievement. Given the trend for performing elective early deliveries for nonmedical reasons, study authors conclude that researchers, clinicians and parents should consider the link between weeks of gestation and school performance.