A cohort study of neural tube defects (NTD) in Denmark covering the first seven years of life.

In the County of Fyn, Denmark, which is a well-delimited region comprising a 10% representative sample of the total population, ten complete one year cohorts of newborn were scrutinized for neural tube defects (NTD). Among 66,000 births, 71 cases with NTD were observed. The total prevalence at birth was 1.08/1,000; 0.29 for anencephaly; 0.20 for encephalocele, and 0.59 for spina bifida (SB). This is at the same level as in other Scandinavian countries. Considering only neonates born alive, 57% of the total survived until the age of 7 years, disregarding anencephaly, but only 4 of 18 SB cases and 6 of 11 encephalocele cases had no handicaps at age 7. On the average, SB patients spent 9% of their life before the age of 7 years in hospitals and encephaloceles 2%. The SB cases occupied 25 times more beds per year than the comparable age group in general and many were likely to need continued medical and social care.