The infant with anencephaly

To the Editor: As the Medical Task Force on Anencephaly has pointed out (March 8 issue),¹ the cause of human anencephaly is still not known, but studies in animals demonstrate that anencephaly results from failure of closure of the anterior neuropore. The third ventricle frequently remains in communication with the amniotic fluid. The lateral ventricles do develop, and cerebral cortical neurons differentiate. One of the more effective means of producing anencephaly in rats is the use of large doses of vitamin A.^{2 3 4} This fact was not mentioned as a cause in the article, but it may be important, particularly in.