Association between early-term birth and delayed neurodevelopment at the age of 2 years: results from a cohort study in China

A growing body of evidence indicates that early-term births (37–38 weeks of gestational age) have an increased risk of short-term and long-term complications. Here, we sought to explore the association between early-term births and the risk of delayed neurodevelopment at age 2 years. Pregnant women and their live singleton birth were recruited from a single tertiary hospital between October 2013 and February 2017. Mental and Psychomotor Development Indexes (MDI and PDI) were assessed using the Bayley Scales of Infant Development (BSID). Delayed neurodevelopment was defined as scores of PDI or MDI less than −1SD relative to the mean score of the study population. In total, 1678 full-term infants and 727 early-term infants were assessed when they were 2 years old. After adjustment for potential confounders, early-term birth was related to 43% increased odds of neurodevelopmental delay in the PDI domain as compared with full-term birth (OR: 1.43; 95% CI: 1.12, 1.82). The observed associations were more prominent among those infants born by cesarean (OR: 1.44; 95% CI: 1.03, 2.00) and among males (OR: 1.66; 95% CI: 1.20, 2.28). No statistical difference in the MDI domain was found between early-term and full-term births.