This site is intended for healthcare professionals
Last reviewed dd mmm yyyy. Last edited dd mmm yyyy
This is a fetal abnormality in which there is no development of the forebrain. The cranial vault is absent, and the anterior pituitary gland may be absent or hypoplastic. It is due to a failure of closure at the cephalic end of the neural tube.
Survival is limited. Brain stem responses permit sucking, feeding, crying and facial grimacing. Many are stillborn, or if liveborn survive only a few hours.
The risk of recurrence of this condition is about 1:30. This rises to about 1:10 if two previous children have been affected.