The family history of uncomplicated congenital hydrocephalus: an epidemiological study based on 270 probands.

A longitudinal study was carried out on the family history of 270 babies with uncomplicated congenital hydrocephalus. They had 453 siblings of whom five (11.1/1000) had congenital hydrocephalus and nine (19.9/1000) neural tube defects. These data, together with those obtained from previously published reports indicate that the aetiology of the two conditions is probably the same in many cases, although there are unusual exceptions in special families even apart from those with the sex linked, recessively inherited hydrocephalus.