Vitamin D status in pregnancy and cord blood is associated with symptoms of attention-deficit hyperactivity disorder at age 5 years: Results from Odense Child Cohort.

In this cohort, serum 25-hydroxyvitamin D <25 nmol/L in cord blood and early pregnancy were risk factors for higher attention-deficit hyperactivity disorder symptom score in 5-year-old children, suggesting a protective effect of vitamin D on attention-deficit hyperactivity disorder traits at preschool age.