Long-term cognition and behavior in children born at early term gestation: A systematic review

Abstract

Introduction: Recent recommendations characterize deliveries at 37⁺⁰ weeks through 38⁺⁶ weeks as early term. We aimed to review the literature systematically on long-term cognition, school performance and behavior in children born early term (37⁺⁰ to 38⁺⁶ weeks) compared with full term (39⁺⁰ to 40⁺⁶ weeks).

Material and methods: The review was performed according to the PRISMA Statement. The final literature search was performed on 31 January 2019. We located studies in PubMed, Embase, CINAHL and Cochrane Library. Eligible studies were randomized controlled trials, cohort studies and case-control studies, with outcome assessment performed at 2-19 years. We collected information using a structured data form and evaluated study quality using the Newcastle-Ottawa Scale (NOS).

Results: We included 42 observational studies published between 2006 and 2018. No restriction on year of publication was made. The mean NOS score was 5.8 with a range from 3 to 9. Compared with children born full term, children born early term had a lower intelligence score in early adulthood and up to some 30% increased risk of attention-deficit/hyperactivity disorder. Furthermore, we found some 10%-40% increased risk of cognitive problems, some 25% higher risk of language impairments and another 8%-75% with poorer overall school performance. No meta-analysis was conducted due to heterogeneity in the outcome measures. Only 10 studies presented subgroup analyses in spontaneous deliveries or adjusted for type of labor onset/induction.

Conclusions: Children born early term are at increased risk of cognitive deficits, poorer school performance and behavioral problems compared with children born full term.

Keywords: behavior; cognition; early term; gestational age; long-term development; school performance.