Prenatal detection of hydrolethalus syndrome.

The prenatal diagnosis of hydrolethalus syndrome is presented on the basis of seven cases. The results demonstrate the primary importance of ultrasonography in the evaluation of this type of malformation. Already in early pregnancy, the intracranial abnormalities and the accelerated growth rate of the fetal head are demonstrable by ultrasound more easily than in ordinary 'simple' hydrocephalus. Diagnostic amniocentesis in early pregnancy proved to be useless because alpha-fetoprotein levels and chromosomal status were normal.