Karolinska Institutet researchers report that children born before 34 weeks of gestation show persistent deficits in cognitive abilities at ages 9 to 10. Impairments appear independent of socioeconomic status, genetic predisposition, and prenatal or child-specific risk factors. Lower scores were observed in vocabulary, working memory, episodic memory, and recall tasks. Children born late preterm (34–36 weeks) or early term (37–38 weeks) performed comparably to those born full term.

Preterm birth affects approximately 13 million infants worldwide each year and remains a leading cause of childhood morbidity and mortality. Although advances in perinatal care have increased survival, cognitive deficits in these children continue to present major public health concerns.

Critical brain development processes that occur between 24 and 40 weeks of gestation may be disrupted by premature birth. Prior research has mostly focused on extremely or very preterm infants, often overlooking those born moderately or late preterm, who constitute a large portion of preterm births.