Objective: To estimate the association between an Apgar score of less than 7 at 5 minutes after birth and long-term cognitive function.
Methods: A linkage between the Swedish Medical Birth Registry and the Swedish School Grade Registry was performed. All singletons born from 1973 to 1986 after 36 6/7 weeks of gestation to Swedish-born women were included. Fetuses that were stillborn, newborns who had congenital malformations or were small for gestational age, and children who died or emigrated before 16 years of age were excluded from the analysis.
Results: The study included 877,618 individuals in the analysis. Newborns with Apgar scores less than 7 at 5 minutes after birth showed a significantly increased risk of never receiving graduation grades, presumably because they went to special schools because of cognitive impairment or other special educational needs (odds ratio 1.93, 95% confidence interval 1.75-2.14). One out of 44 newborns (numbers needed to harm) with an Apgar score of less than 7 at 5 minutes after birth will go to a special school because of the antenatal or perinatal factors that caused the low Apgar score. Nearly all school children who had Apgar scores of less than 7 at 5 minutes after birth showed an increased risk of graduating from compulsory school without graduation grades in that specific subject or receiving the lowest possible grades and were also less likely to receive the highest possible grade.
Conclusion: An Apgar score of less than 7 at 5 minutes after birth is associated with subtle cognitive impairment, as measured by academic achievement at 16 years of age.
Level of evidence: II.