title: Anencephaly and spina bifida: two unsolved problems.
mesh_terms: D000757:Anencephaly / Q000196:embryology / Q000209:etiology* / Q000517:prevention & control; D006801:Humans; D007231:Infant, Newborn; D016135:Spinal Dysraphism / Q000196:embryology / Q000209:etiology* / Q000517:prevention & control