Cerebral disorders in the first 7 years of life in children born post-term: A cohort study

Background: To estimate the association between post-term delivery and risk of physical disabilities, mental disabilities, and seizures during the first 7 years of life. Methods: Data from 57,884 singleton infants born alive in week 39-45 by mothers included in the Danish National Birth Cohort (1997 to 2004) were analyzed, of these 51,268 were born at term (39-41 + 6) and 6616 post-term (42 + 0-44 + 6). Information on clinical endpoints was obtained from an interview at 18 months of gestational age, from a 7-year questionnaire, and from the Danish National Patient Register. Logistic regression and Cox regression were used to estimate odds ratios and hazard rate ratios for the outcome obtained from the interview/questionnaire data and from the register-based data, respectively. Results: We found no statistically significant increased risk of physical disabilities, mental disabilities, and epilepsy among children born post-term, though for most outcomes studied a tendency towards more adverse outcomes was seen. When children born late term (week 41) were compared to children born in week 42 or later the same tendency was found. Conclusion: Post-term born children had a tendency to an excess risk of neurological disabilities as followed for up to 7 years of age.